'A^^£i'Siiff-.-'.'?::g^«a!ii RART V GEOLOQY AND AGRICULTURE^ A Preliminary Report THE GEOLOGY OF LOUISIAM GILBERT D. HARRIS, Geologist-in-Charge n) AND A. C. VEATCH, Assistant Geologist MADE UNDER DIRECTION OF STATE EXPERIMENT STATION, BATON ROUGE, LA. WM. C. STUBBS, Ph.D., Director Sc, Q£/f7 AIZH2 LOUISIANA STATE UNIVERSITY AND A. AND M. COLLEGE. Louisiana State Board of Agriculture and Iinmig7'ation. Ex-Officio. GOVERNOR MURPHY J. FOSTER, President. WILLIAM GARIG, Vice-President Board of Supervisors. LEON JASTREMSKI, Commissioner of Agriculture and Immigration. THOMAS D. BOYD, President State University. WILLIAM C. STUBBS, Director State Experiment Stations. Members. JOHN DYMOND. Belair, La. Judge EMILE ROST, St. Rose, La. A. V. EASTMAN, Lake Charles, La. CHAS. SCHULER. Keachie, La. E. T. SELLERS, Walnut Lane, La. H. P. McCLENDON, Amite City, La. Station Staff. WM. C. STUBBS, Ph.D., Director. R. E. BLOUIN, M.S., Assistant Director and Chemist, Audubon Park, New Orleans, La. J. G. LEE, M. S., Assistant Director, Calhoun, La. H. E. WRIGHT, B.S., Chemist, Audubon Park, New Orleans, La. C. E. COATES, JR., Ph.D., Chemist, Baton Rouge, La. J. F. HARP, B.S., Assistant Chemist, Baton Rouge, La. M. BIRD, M.S., Chemist, Calhoun, La. SIMON BAUM, B.S., Assistant Chemist, Audubon Park, New Orleans, La. ROBT. GLENK, B.S., Chemist, Baton Rouge, La. Prof. G. D. HARRIS, Ph. B., Geologist in charge of Geological Survey, Audubon Park, New Orleans, La. A. C. VEATCH, Assistant Geologist, Audubon Park, New Orleans, La. W. R. DODSON, A.B., S B., Botanist, Baton Rouge, La. H. A. MORGAN, B.S.A., Entomologist, Baton Rouge, La. F. H, BURNETTE, Horticulturist, Baton Rouge, La. W. H. DALRYMPLE, M.R.C.V.S., Veterinarian, Baton Rouge, La. GEO. CHIQUELIN (Grad. Audubon Sug. Sch. ), Sugar Maker, Audubon Park, New Orleans. La. WM. D. CLAYTON, M.S., Farm Mgr., Audubon Park, New Orleans, La. JAS. CLAYTON, Farm Mgr., Baton Rouge, La. T. I. WATSON, Farm Mgr., Calhoun, La. J. K. McHUGH, vSecretary and Stenographer, Audubon Park, New Orleans, La. H. SKOLFIELD, Treasurer, Baton Rouge, La. The Bulletins and Reports will be sent free of charge to all farmers by applying to Commissioner of Agriculture and Immigration, Baton Rouge.La. CONTENTS Letters of Transmission Prefatory Remarks Plans of Operation SECTION I HISTORICAL REVIEW BY Harris and Veatch SECTION II GENERAL GEOLOGY BY Harris and Veatch SECTION III SPECIAL PAPERS BY Various Authors Office of Experiment Stations, Louisiana State University and A. and M. College, Baton Rouge, La., October, 1899. To His Excelle^icy Murphy J. Foster, Governor of Louisiana, and President of Board of A gri culture : Sir: Since our last report of the Geological and Agricultural Survey, a complete change has taken place in the personnel of the survey. Prof. W. W. Clendenin, who performed the duties of Professor of Mineralogy and Geology in the Louisiana State University and A. and M. College, and geologist for the stations, has severed his connections with both institutions by resignation, and taken charge of Blees' Militarj^ Academy, at Macon, Mo. Upon his resignation arrangements were made with Prof. Gilbert D. Harris, Ph.B., of Cornell University, who is the recognized authority of this country in Tertiary geology, by which he was to conduct the survey under our direction and publish annually a report of his work. He gives considerable time to the actual field work and writes and superintends the publication of his reports. Mr. A. C. Veatch has been selected as his assist- ant and gives his entire time to the field and office work of the survey. Mr. Veatch is an acknowledged authority upon Quar- ternary geology, and with his assistance we feel satisfied that the entire State, which consists almost exclusively of tertiary and quarternary formations, will be correctly and fully reported. These two gentlemen have persistently followed their work through freezes and sunshine, over intolerable roads, impelled by an enthusiasm known only to lovers of science. How well they have accomplished their work, the present volume will testify. Collections of typical soils have been made and are being analyzed both physically and chemically in the laboratories of the stations. Besides the above, in November next Prof. Milton Whitney will place in the field two or more soil physicists who will make an accurate soil survey of the State, and in his labora- tory make the physical analyses of all these soils, giving the results to us for publication. It is hoped and believed that in Letters of Transmission. 5 this way a copious volume giving full information of the proper- ties of all the soils of the State, with accurate soil maps, will ultimately be given to the public. Such a work will be of incal- culable benefit to the agriculture of the State besides serving as a guide in giving directions to the various farmers and planters who seek daily knowledge relative to the capacity and require- ments of their soils for growing various crops. The within report covers the following subjects, viz.: Review of the Geological Work already done in the State, General Geol- ogy of the State, and Special Reports, including variolas topics of economic and scientific interest. (See Section III.) It is found difficult to carry on so extensive and important a work as this upon the limited appropriation now received. To cover accurately an area of 45,000 square miles, giving the var- ious geological horizons ; the agricultural and forest resources ; the mineral and underground resources, and the water supplies, both for drinking, irrigation and navigation, requires a large amount of time and the best scientific talent, and money is required for the successful accomplishment of such a huge task. In fact, a geological and agricultural survey can hardly ever be called completed. Increasing population, progress and enter- prise are demanding the solution of problems constantly arising, and the State should always be ready to lend its assistance. With increased appropriations, the work on hand could be more rapidly prosecuted and the information gathered thereby the more speedily given to the thousands who are seeking homes in our State ; to say nothing of the great value to the hundreds of thousands now residents in our borders. I trust that sufficient funds will be appropriated to permit of a more rapid and extensive prosecution of the work under the able and enthusiastic men now employed in this survey. Respectfully submitted. WM. C. STUBBS, Director. LETTER OF TRANSMISSION Dr. Wm. C. Stubbs, Director State Experiment Stations, Baton Rouge, I,a. Sir : I herewith present you a Preliminary Report on the Geology of Louisiana. Mr. A. C. Veatch acting as assistant geologist, commenced field work November ist, 1898, and studied the distribution of the soils of Caddo and Bossier parishes until my arrival in the State, December 23d. Thereafter we worked for the most part together in De Soto, Sabine, Natchitoches, Grant, Winn, Cald- well and Ouachita parishes. After my departure from the State, the last of March, Mr. Veatch continued work in the northern tier of parishes between Ouachita river and Red river until requested by you to visit the Five Islands and the Sulphur region of the southwestern part of the State. This done, we worked on the report herewith trans- mitted from mid-summer to late autumn, when he again took the field and I saw to the completion of the report. I gladly take this opportunity to inform you that Mr. Veatch has in all his connections with this survey, shown himself a most capable and energetic assistant; and it is to his untiring zeal, and your never failing and well directed support that such suc- cess as the survey has been able to attain is largely due. Most respectfully submitted, GILBERT D. HARRIS, Geologist-in-Charge. Cornell University, Ithaca, N. Y., \ Nov. 25, 1899 \ PREFATORY REMARKS Plans of Operatiox The prosecution of a well organized geological survey demands an expenditure of funds far in excess of those now at our com- mand. This the reader is requested to constantlj^ bear in mind. With much volunteer labor, however, we have been able to bring together, in this report such data as we believe will be of service to those who in the future shall investigate special prob- lems relating to the geology of Louisiana. This remark applies more particularly to Section land portions of Section II. They show what has already' been accomplished, by whom, and where. They might well be styled a summary' of geological reconnais- sance work in Louisiana. Part III contains the beginnings of some of the special lines of investigation that this Surve}^ will, we hope, be able to take up and carry out. They include : (i) The mapping geographically, topographically, and geo- logicall3% of certain areas that are of special interest either (a) on account of the large number of inhabitants thej' contain and to whom such maps would be of service, or (b) on account of some speciall}' interesting geological phenemenon they exhibit, or (c) on account of their proximitj' to seats of learning where they will be of service to teachers who wish to teach geology from their own surroundings — the onl}- true way. Detailed reports should accompany these sheets. (2) The gathering of information for agricultural or soil maps, as has been explained in Dr. Stubb's letter heretofore affixed. (3) The working out of the stratigraphic relations of the various deposits of Louisiana. This can be done by (a) study- ing with great care the fossil remains found in the various for- mations and hence identifying deposits bj' the fossils they con- tain, (b) by putting down test wells and observing the nature of the different beds passed through, (c) by studying the stratig- 8 Geological Survey of Louisiana raphy of natural sections, along rivers and smaller streams of water. U ntil a thorough knowledge is obtained of the way the different deposits lie in the State, all questions relating to artesian waters, extent of mineral deposits, origin of soils, etc., are unanswer- able. (4) The determination of meridian lines and of the amount and direction of magnetic forces within the boundaries of the State — primarily for the assistance of land-surveyors. (5) The investigation of the different mineral products of the State. (6) The encouragement of road improvement. So far as (i) is concerned, the earliest cooperation with the U. S. Geological Survey should be sought. The State would pay for but half of the field expense of topographic work, the general Government doing all the rest. Cooperation has already been secured for work outlined under (2). The Coast Survey is ready to cooperate as regards work under (4) and its aid should be early sought. In case funds are not forthcoming for the prosecution of all these lines of work, then some will be discarded and such as seem most urgent will be continued. It rests with the people to say how much can be invested in work of this nature, and with the Geologist- in-Charge to see that due returns are made for the investment, be it great or small. Section I HISTORICAL REVIEW BY HARRIS AND VEATCH HISTORICAL REVIEW CONTENTS PERIODS OF INVESTIGATIONS First Period From The Earliest Explorations to the Year 1867 Page Page Earliest explorers 11 Demeril 18 Coxe II Carpenter 18 Bartram 12 Owe?i 19 Dunbar 12 Talcott 19 Stoddard • •. • 1*3 Jones 19 Darby 14 Lyell 19 Nuttall 15 Dickson and Brow7i 20 Graham 15 Drake 21 Delafield 15 Ellet 21 Harlan 16 Thomassy 21 Morton 17 Humphreys and Abbott 22 Conrad 18 Owen 23 Second Period Reconnaissance Period, 1S67-1892 Hilgard 23 Gabb 37 Hopkiyis 32 Johnson 37 Edwards 36 Knowlto7i 38 Hayes 36 Leidy 38 Forshey 37 Third Period Period of Work Done Under the Direction of the Experiment Stations Lerch 39 [ 'aughan 42 Harris 41 Clcndeniii 43 Cope 42 Jolnison 43 HISTORICAL REVIEW PERIODS OF INVESTIGATION First Period From the Earliest Explorations to the Year 1867 Earliest explorers. — Few and desultory indeed are the contri- butions made to the geological literature of this State up to the middle of the present century. As might naturally be expected, it was the Mississippi, the great river, that first attracted and held the attention of the earliest explorers and naturalists in this region. Commerce dictated that its mouths should be explored and mapped at an early date, and in 1722 P. Charlevoix accomplished this task in a highly creditable manner.* He argued in a truly scientific spirit that "the quantity of shoals and little islands that have been seen to form in the various mouths of the river during the past twenty years" leave no doubt as to the manner and comparatively recent date of forma- tion of the lower delta region. Coxe. — If the reference of Coxe to the River Natchitock can be taken to mean the Red river, and it seems quite probable that they are the same, the salt springs in northern Louisiana were known and worked in the very early history of this country. He says, " Ten or twelve leagues higher on the west side," [of the Mississippi] ' ' is the River Natchitock, which has a course of many hundred miles ; and after it is ascended about one hun- dred, there are many springs, pitts, and lakes which afford most excellent common salt in great plenty, wherewith [the Indians] trade with neigboring nations for other commodities they want. Upon the river inhabit not only the Nachitocks, Naguteeres, Natsohocks but higher several other nations."! On the next * Thomassy, Geologic Pratique de la Louisiaiie accompagne de6 planches, New Orleans and Paris, 4°, 263 pp., figs,, i860. See pp, 27-28. t A description of the English province of Carolina, by the Spainards called Florida and by the French La Louisiane, and also of the great and famous River Meschacebe, or Missisipi, and the five vast navigable lakes 12 Geological Sur\ev of Louisiana [Sect. river above the river of the Natchitocks live the "Arkansas, a mighty nation." Bartram.'^ — In 1773 Win. Bartram started on his journey of the Southern States ' ' for the discovery of rare and useful pro- ductions of nature, chiefly in the vegetable kingdom." He passed through Lake Pontchartrain and ascended the Mis- sissippi as far as Point Coupe. The plainsf near Port Hudson he described as showing " whitish clay or chalk, with veins of sea-shells, chiefly of those little clams called les coquelles \^Ra7i- gia\ interspersed with the white earth or clay, so tenaceous and hard as to render it quite sterile." He described the Port Hudson^ bluff as consisting of strata of various colors, white, red, blue, purple sand, marl and chalk. He observed the cypress stump stratum at the base of the cliff, and comments on the same as follows: "These stumps are sound, stand upright, and seem to be rotted off about two or three feet above the spread of the roots ; their trunks, limbs, etc., lie in all directions about them. But when these swampy forests were growing, and by what cause they were cut off and over- whelmed by the various strata of earth, which now rise near one hundred feet above, at the brink of the cliff, and two or three times that height but a few hundred yards back, is a phenom- enon not easily developed." Dunbar. — In 1801 Wm. Dunbar, of Natchez, sent a letter to the president of the American Philosophical Society, extracts of which were published in the Transactions for that year (vol. vi, of fresh water and the parts adjacent. Together with an account of the commodities of the growth and production of the said province. And a preface containing some considerations of the consequences of the French making settlements there. By Daniel Coxe. Second edition. London 1726. See pp. ic-ii. *Travels through North and South Carolina, Georgia, east and west Florida, the Cherokee country, the extensive territories of the Musco- gulges, or Creek Confederacy, and the country of the Choctaws ; contain- ing an account of the soil and natural productions of those regions, together with observations on the manners of the Indians Embellished with cop- per plates. B3- Wm. Bartram, Phila., 1791. tibid. p. 431. ilbid. p. 435 I] Historical Review: First Periods 13 pp. 40-42) recounting the discovery of fossil bones to the west of the Mississippi, supposed to resemble those of the big bone lick near the Ohio. Two years later he forwarded to the same society (see vol. vi, pp. 55-58) a letter received from Martin Duralde from the ' ' country of the Apelousas ' ' relating to the occurrence of fossil remains, supposed to be elephant bones, in that region. Fur- thermore, " M. Duralde in sinking a well in his cow-yard found sound oyster shells, lying in a horizontal direction, near to each other, at a depth of 22 feet." In 1804, Dunbar contributed an extended article to the same Transactions (pp. 165 et seq.) entitled "Description of the River Mississippi and its Delta, with that of the adjacent parts of Louis- iana." This contains little of geological interest. Stoddard* — In his Sketches of Louisiana, Maj. Stoddard comments as follows on the delta regionf : "Nothing is more certain than that the delta has gradually risen out of the sea, or rather that it has been formed by alluvion substances, precipi- tated by the water from the upper regions. It is calculated that from 1720 to 1800, a period of eighty years, the land has advanced fifteen miles into the sea ; and there are those who assert, that it has advanced three miles within the memory of middle aged men." His notice of the Five Islands reads as follows : "There is an island of about three miles in circumference, situated in the gulf a few miles to the westward of the mouth of the Chafalia, ele- vated more than two hundred feet above the level of the sea and connected with the mainland by a sea marsh. Most of the islands along the shores of the Mexican gulf exhibit this proud pre-eminence, while the country for a great depth is most of the time covered with water. Some of them are impregnated with sulphur, and one of them has been known to be on fire for at least three months." The production of the saline springs near Natchitoches is given *Sketches, Historical and Descriptive, of Louisiana. By Major Amos Stoddard. Phila. 1812. flbid. p. 158. 14 Geological Survey of Louisiana [Sect. as about two hundred and forty barrels of salt per month.* On page 1 86 the cause of the rapids at the site of Alexandria is ascribed to "two ledges of hard indurated clay, or soft rock which extend across the channel at about three-fourths of a mile from each other." Lignite also receives notice in this work. He says : "Stone or pit-coal is an article of some importance It fre- quently makes its appearance on the Washita, the Sabine, and the Red river, particularly on the borders of a lake in the neigh- borhood of Nachitoches. This article is of use to smiths, even at this time, and its importance will increase as the country becomes more populous and the villages enlarge."! Darby. X% — Though Darby's works were of a general nature as the titles indicate he wove in many geological facts and observa- tions quite in advance of anything that had preceded his works and in fact by no means equalled by many of his successors. He calls attention to the salt deposits on the Saline (Drake's) (see Geog. La. pp. 29 and 211 and Emigrant's p. 89) on the land of Mr. Postlethwait. He describes the occurrence of dead cypress trees in Lake ■^Ibid. p. 400. flbid. pp. 391-392- :{:A Geographical Description of the State of Louisiana : presenting a view of the vSoil, Climate, Animal, Vegetable and Mineral Productions, Illustra- tive of its Natural Physiognomy, its Geographical Configuration, and Rela- tive Sitiiation : with an account of the Character and Manners of the Inhabitants. Being an Accompaniment to the Map of Loi^isiana. By William Darby. Phila., i8r6. §The Emigrant's Guide to the Western and Southwestern States and Territories ; comprising a Geographical and Statistical Description of the States' of Louisiana, Mississippi, Tennessee, Kentucky, and Ohio; the Territories of Alabama, Missouri, Illinois, and Michigan ; and the western parts of Virginia, Pennsylvania and New York. With a complete List of the Road and River Routes west of the Alleghany Mountains, and the con- necting roads from New York, Philadelphia, and Washington City to New Orleans, St. Louis and Pittsburg. The whole comprising a more compre- hensive Account of the Soil, Productions, Climate, and present state of Improvement of the Regions described, than any Work hitherto published. Accompanied by a map of the LTnited States, including Louisiana. Pro- jected and Engraved expressly for this work. By W^illiam Darby, New York, 1818. I] Historical Review : First Period 15 Bistineau (Geog. La. pp. 31-32) and attributes the origin of this and similarly located lakes to the choking up of small stream valleys by Red river sedimentation. On pp. 45-46 the occurrence of rocks (now called Grand Gulf) on the Ouachita river on the western angle of Sicily island is noted and they are properly correlated with similar exposures on Red river at Alexandria. He mentions also rock exposures on the Sabine, p. 23, but does not correlate the same with the Sicily island beds. He describes with care the river systems of the State and dis- cusses at length the various prairies in the southwestern part of the State. He noticed marine shells in the banks of Red river, propably at the now well-known locality at Montgomery.* His description of the Five Islands is much more complete and exact than Stoddard's, being based on a personal examina- tion of Petite Anse. He noted the existence of a salt spring on Petite Anse from which salt had been manufactured.! Nuttall. — In 182 1 Thomas Nuttall mentions ferruginous con- glomerate resembling the New Jersey conglomerate (afterwards referred to the Cretaceous by Morton) as extending for more than a thousand miles above Alexandria, J This seems to have been the first of the early erroneous references of Louisiana material to the Cretaceous. Graham. % — The reports of the general land office for 1824 give the location by townships of two salt springs in the region north of Red river. "One in township No. 12 of range No. 5 West" (probably Drake's). " The other in township No. 13 of range No. 4 West " (Price's). Delafield.\ — A good description of the topographical features of the mud-lumps of the passes of the Mississippi was given by * Geographical Description of Louisiana, p. 48. t Emigrant's Guide p. 68, ifjour. Phila. Acad. Sci., ist series, vol. 2, p. 46. tiGeorge Graham, Report of the Commisssioner of the general Land OfHce in Relation to Lead Mines and Salt Springs. i8th Cong, ist Sess., House Ex. Doc, vol. 6, No. 128, 1824, pp. 14-15. II Report on the Survey of the Passes of the Mississippi, 21 Cong., ist Sess., House Ex. Doc. No. 7, vol. i, pp. 7-14, 1829. Reprint, 39th Cong, ist. Sess., House Ex. Doc. No. 97, vol. 12, pp. 2-3, 1866. i6 Geological Survey of Loulsiana [Sect. Richard Delafield in 1829. Their life history is also fully- described. An examination in the early part of the same year by Bernard and Poussin resulted in a very brief description of the character of the material thrown out of the lumps.* Harlan. — The first contribution to the systematic geology of the State may be regarded as Article XII in the Transactions of the American Philosophical Society, vol. 4, New Series, 1832, p. 397, et seg., entitled " Notice of Fossil Bones found in the Tertiary Formation of the State of Louisiana. By Richard Harlan, M.D., etc. Read October 19, 1832." Dr. Harlan here describes some of the large fossil bones sent him by Judge Bry ' ' found on the Ouachita river in the state of Louisiana, at a distance (south) of about fifty miles by land, and one hundred and ten by water from the town of Monroe, in the parish of Ouachita, and in lat. 31° 46' or 48'." Judge Bry 's comments on the geology of northern Louisiana are as follows : " The hills, beginning at Cataouta, extend north to the Arkansas river and west to Red river, whence they spread to the Sabine. Through that country are interspersed over- flowed lands varying in extent according to the magnitude of the creeks, of which they form the bank at low water, and which flow over them at high water. In these hills very few ores are found except those of iron, which are abundant in two different places ; but no measures have been taken to ascertain their value. The highest of the hills do not exceed eight hundred feet above high water mark ; and in many places they dwindle into gently rolling ground. These hills appear to be of a much more ancient formation than the lower section of Louisiana. No rocks, however, enter into their composition ; but a few sandy stones and pebbles, nearly all siliceous, are occasionally seen scattered on their summits, or in the beds of the numerous creeks fed by springs issuing from them. ' ' Sea shells are discovered in several places ; I found them on the highest ridge which divides the waters running into the Red river from the tributary streams of the Ouachita. The tract, by far the richest in calcareous substances, is the one *22d Cong. 1st Sess., House Ex. Doc, vol. 4, No. 185, 1832. I] Historical Review : First Period 17 within the limits where the fossil bones have been found, extending about fifteen miles from north to south, and probably ten or twelve from east to west. Several years ago, while rambling among these hills, I met with a small creek, the banks of which are in some places thirty feet high, in which I found many different species of sea shells, among others, pectenites, belemyiites , etc. At the same time, my attention was attracted by a large quantity of cornua arninoyiis^ the largest of which did not exceed an inch and a half in diameter, while many were much smaller. " The hill, in which the bones herewith presented were found, is within the limits above described, at a distance of not more than two hundred yards from the Ouachita river. About three years ago, after the occurrence of a long spell of rainy weather, a part of the hill slid down near the water's edge, and thereby exposed twenty-eight of these bones, which had been until then covered by an incumbent mass of earth about forty feet thick. They were embedded in a bank of sea marl, a specimen of which is added to the bones, as well as the calcareous spar and talc also found in the same hill. I followed the horizontal vein of this marl, five or six inches thick, which I traced to a distance of about forty feet, when it sinks into the valley under an angle of from twenty-five to thirty degrees. It appeared to have effloresced where it had been long exposed to the influence of the atmosphere. "When these bones were first seen, they extended in a line, which, from what the person living near the place showed me, comprised a curve, measuring upwards of four hundred feet in length, with intervals which were vacant. The person referred to destroyed many of the bones by employing them instead of andirons in his fire place and I saved what remained from the same fate. I think, however, that a great many more bones belonging to the same animal are yet covered, and will gradually appear, as the soil and the marl shall be washed off by the rain." Harlan was of the opinion that the bones under consideration were of a huge lizard-like reptile and proposed for the animal represented the name "' Basilosau7-2is." Morton. — The following year Morton concluded from the fos- i8 Gp:olo(;ical Survey of Louisiana [Sect. sils mentioned in Dr. Bry's letter that the material represented was Cretaceous, and from a letter received from Dr. Pitcher states that the ' ' ferruginous sand formation ' ' (Cretaceous) out- crops between Alexandria and Natchitoches.* It is hardly nec- essary to remark that neither of these statements is supported bj' our present knowledge of that region. Conrad. — In the Journal of the Philadelphia Academy of Natural Sciences, vol. 7, 1834, p. 120, T. A. Conrad refers to the shells found in connection with the Basilosaunis to the Eocene series, and states that the commonest fossil is Corbula 07iiscus, a common Claiborne fossil. He states that the bones were doubtless from a nearby Cretaceous stratum, not from the the Eocene as stated by Harlan. In the Proceedings of the Philadelphia Academy of Natural Sciences for 1841, p. 33, Conrad describes one of the mollus- can species found at the same locality. He names it Cardiinn jiicolleti and. gives its provenance as " Green clay, 50 feet high, right bank of the Washita river, Monroe County, La." The same fossil is described on p. 190, vol. 8, of the Journal of the same society. Demeril.'\ — Harlan's description of the Basilosaurus soon attracted the attention of the French savants. M. Demeril in 1838 pointed out the true character of the animal. He says, " As to the Basilosaunis presented for comparison, it must be admitted that the vertebrse believed to have come from this fossil seem rather to be from a cetacean than a reptile. ' ' Carpenter. — During the same period William Carpenter was gathering together information on the geology of the southern part of Louisiana. He records the finding of vertebrate remains in two localities. One on little Baj'ou Sara in the parish of West Feliciana where he found teeth and fragments of the jaw of a mastodon, and a tooth of an Eqims, much larger than the modern horse. This he figures in the American Journal of Science, vol. *Am. Jour. Sci., vol. 23, pp., 288, 1833. Also Synopsis of the Organic Remains of the Cretaceous Group of the United States, by Samuel George Morton. Phila., 1834. fCompte Rendu des Seances de I'Academie des Sciences, Oct. 22, 1838, Paris. I] Historical Review : First Period 19 34, p. 203, 1838. The other near Opelousas where mastodon bones were also found.* He described with considerable detail the Port Hudson section, and traced in the Florida parishes, the northern limit of what is now called the Port Hudson group. f Owen. — Dr. Harlan had received later on some more perfect specimens of his Basilosaurus from Alabama and these he took with him to lyondon in 1839, and submitted them to Richard Owen, who proved to the satisfaction of all that the huge mon- ster was an aquatic mammal of dugong, or whale-like a£5nities. He gave the name Zeuglodon cetoides to the species. His studies and conclusions are given at length on pp. 69-79, Trans. Geol. Soc, IyOnd.,vol. 6, 1842. Talcott. — The subject of rendering the mouths of the Missis- sippi navigable to vessels of deep draught seems to have agitated the public mind from an earl}- date. The report of Joseph G. Totten to the war department in 1839 contains a very accurate map of the mouths of this river, and drawings of two of the mud lumps by Captain Andrew Talcott. + Jones. — In the Journal of the Franklin Institute, 3d series, vol. 2, 1841, pp. 83, Engineer A. C. Jones gives a very accurate description of the physical characters of the mud-lumps at the mouths of the Mississippi. Z,j'^//.— The Athenaeum Journal for Sept. 26, 1846, contains an article by Sir Charles L,yell ' ' On the Delta and Alluvial Deposits of the Mississippi, and other points in the Geology of North America observed in the years 1845, 1846." This was repub- lished in the Report of the British Association for the Advance- ment of Science for 1847, vol. 16, pp. 117-125. An abstract of the same occurs in the American Journal of Science, 2d series, vol. 3, 1847, pp. 34 and 118. Herein the author states that he doubts whether the delta advances over one mile a century into the gulf. On p. 36 (A. J.S.) he states that the matter held in suspension by the waters of the Mississippi is about yyVt ^^^ weight of the water itself. On p. 118 he changes the proportion to y-Vtt- *Am, Jour. Sci., vol. 35, pp. 345-346, 1838. fAm. Jour. Sci., vol. 36, pp. 118-124, 1839. JSenateDoc, No. 463, 26th Con., istSess., vol. 7, 1840. 20 Geological Survey of Louisiana [Sect. In volume 2 of his Second Visit to the United States, pub- lished (3d ed.) 1855, Lyell (p. 153) is greatly impressed with the stability of the general features of the mouths of the Missis- sippi, and concludes that "we must allow an enormous period of time" for the accumulation of the material constituting the whole delta. On p. 250 he estimates 67,000 years for the time required for the formation of the delta. On pages 180-182 he describes the interesting bluff at Port Hudson after quoting largely from Bartram and Carpenter. Natchez bluff is next described (p. 194) as follows : "The lower strata, laid open to view, consist of gravel and sand, destitute of organic remains, except some wood and silicified corals, and other fossils, which have been derived from older rocks ; while the upper sixty feet are composed of yellow loam, presenting as it wastes away, a vertical face towards the river. From the surface of the clayey precipice are seen projecting in relief, the whitened and perfect shells of land snails of the genera Helix, Heli- ci7ia. Pupa, Cyclostoma, Achatina and Sticciyiea. These shells of which we collected twenty species, are all specifically identical with those now inhabiting the valley of the Mississippi. " The resemblance of this loam to that fluviatile slit of the val- ley of the Rhine, between Cologne and Basle, which is generally called "loess" and "lehm" in Alsace, is most perfect. In both countries the genera of shells are the same, and as, in the ancient alluvium of the Rhine, the loam sometimes passes into a lacus- trine deposit containing shells of the genera Lyninaa, Planorbis, and Cyclas, so I found at Washington, about seven miles inland or eastward from Natchez a similar passage of the American loam into a deposit evidently formed in a pond or lake. It con- sisted of marl containing shells of LymncEa, Planorbis, Paludina, Physa and Cyclas, specifically agreeing with testacea now inhab- iting the United States." He records Mastadon, Megalonyx, horse, stag, etc., from these loams. Dickeson a7id Brown. — At the first meeting of the American Association for the Advancement of Science held at Philadelphia in 1848, Dr. Dicke.son read a joint paper on "The Sediment of the Mississippi," in which the statement is made that the delta of the Mississippi has been no less than 14,204 years in forming. (See p. 51, Proc. Am. Assoc. Adv. Sci., vol. i.) I] Historical Review : First Period 21 Drake.^ — In a volume entitled the " Principal Diseases of the Interior Valley of North America," Dr. Daniel Drake succeeded in weaving in many facts and statements of geological interest. His description of the mud lumps (pp. 91-94) is particularly good and deserves attention because he advances the gas theory for the formation of these objects. He gives (p. 71) a well sec- tion on Lake Pontchartrain and the section exposed in the gas tank excavation at New Orleans. On page 161 he states that the geological formation about Fort Jessup is Tertiary. Ellet. — In 1853 appeared a somewhat extensive work on the lower Mississippi by Charles Ellet, C. E.f This book is severely criticised by Jones in the Journal of the Franklin Institute, vol. 26, 1853. (See pp. 60 and 162.) Thomassy.\ — In i860, Reymond Thomassy published his " Geologic Pratique de la Louisiane," both in this country and in France (Paris). Whatever may be said of the use of the word ' ' pratique ' ' in his title, Thomassy had access to and used to good advantage the earlier rare contributions to the cartography of Louisiana. His geology, was in the main limited to a discussion of the role the Mississippi river has played in the formation of the so-called delta region of the State. Particularly was he impressed with the multifold manifestations of water absorption all along the Mississippi and its consequent diminution in volume gulf-wards, and the appearance of lateral springs, lakes and terminal mud- lump volcanoes, all having their origin in the porosity of the grounds of southern Louisiana and the consequent subter- ranean flow of large quantities of water. * A Systematic Treatise, Historical, Etiological, and Practical, on the Principal Diseases of the Interior Valley of North America, as they appear in the Caucasian, African, Indian and Esquimaux varieties of its popula- tion. By Daniel Drake, M.D., Cincinnati, 1850. t The Mississippi and Ohio Rivers ; containing plans for the protection against inundations and investigation of the Practicability and cost of improving the Navigation of the Ohio and other rivers by means of Reser- voirs ; with an appendix on the bars at the mouth of the Mississippi, 8°, 367 pp., 1853, Lippincott & Co., See Review in Jour. Franklin inst., 3d series, vol. 25, pp. 360. X Geologic Pratique de la Louisiane par R. Thomassy. ( Accompagne de 6 planches.) Chez 1 'auteur a la Novella-Orleans, et a Paris, i860. 22 Geological Survey of Louisiana [Sect. Chapter VIII, he devotes to a discussion of the Five Islands, under this caption : "Intervention of Hydro-Thermal and Vol- canic Forces in the Formation of Lower Louisiana." (See special discussion of this subject, special report No. 3.) Humphreys and Abbott.'^ — By far the most serious study of the lower Mississippi in all its bearings, is that by Humphreys and Abbott, first published in 1861 and afterwards with additions in 1876. The hydrography and geology of the whole Mississippi basin are taken into account in order to form just conclusions regarding the special subjects under consideration. They hold that the river alluvium is a comparatively thin stratum underlaid by blue clay of wide geographical distribution and of Tertiary or even Cretaceous age. It is said to underlie the Vicksburg bluff, the whole Yazoo bottom, and to underlie New Orleans at a depth of not more than 40 feet. It forms the bar of tough clay across the efflux of the Atchafalaya 35 feet below the bank and 15 feet below Gulf level. An artesian well boring in the Atchafalaya upon Gen. Welles' plantation, 10 or 15 miles south of Alexandria shows that the alluvial soil there is 30 feet thick, the surface of the older formation being about 50 feet above tide. For an extensive review of this work see Amer. Jour. Sci., vol. 33, 1862, p. 181 ; vol. 35, 1863, p. 223 ; vol. 36, 1863, pp. 16 and 147. In the edition of 1876, pp. 465-466, it is stated that the "original mouth " of the Mississippi was near the efflux of the Plaquemine, 220 miles from the Gulf. By comparing Talcott's maps, 1838, and the U. S. Coast Survey maps of 1851 it is found that the yearly advance of all the passes is 262 feet per annum. The total advance from the Plaquemine efflux has taken 4,400 years. * Report on the Ph^-sics and Hydraulics of the Mississippi River ; upon the protection ot the aUuvial region against overflow and uporf the deepening of the mouths. Based upon surveys and investigations (etc.) U. S. Army, Corps of Topographical Engineers, Professional papers. No. 4, xiii, 456, cxlvi pages, 20 plates, 4°, Philadelphia, 1861 ; also Washington, 1867. Again 214 pages, i plate, Washington, 1867. With additions, 691 pages, 25 plates (Professional papers, No. 13), Washington, 1876. I] Historical Review : vSecond Period 23 Oiven.'^ — Dr. Richard Owen of Indiana visited Petite Anse in the latter part of 1865. After a hast}' examination he showed that the island was composed of sedimentar}- material and con- cluded that it was a wind and wave formed dune similar to those on the southern shore of Lake Michigan. SECOND PERIOD Reconnaissance Period, i 867-1 892 Hilgard. — In 1867, Hilgard, under the direction of the Smith- sonian Institution made a trip down the Mississippi and to the central three of the Five Islands. The preliminar}^ report on this reconnaissance appeared in 1869.;!: At that time he regarded the rock salt as having been formed by evaporation in a lagoon or series of lagoons and as resting in a bed of marine clays of early Quaternary age. He considered the hills as simply the accidents of differential erosion. The same year he published in the American Journal of Science the " Summary Results of a late Geological Reconnaissance of Louisiana." It was based on operations largely in the western part of the State and was made under the auspices of the New Orleans Academj^ of Sciences. Thirty days only were allowed for the field work. New Iberia, Bayou Chicot, Lake Charles, Sabinetown, Many, Mansfield, Coushatta Chute, Winnfield and Harrisonburg were passed through en route. He reviews the various terranes of the State, commencing with the younger or " Port Hudson group " and notices in turn the other groups, viz.: the "Orange Sand formation," the ' ' Grand Gulf group ; " ' the ' ' Vicksburg group ; ' ' the ' ' Mansfield group ;" and then takes up and discusses the salines of North Louisiana and the artesian wells of Calcasieu. The Port Hudson group is said to be of considerable thickness, 600 feet or more beneath New Orleans and to extend up the *On the Rock Salt at New Iberia, Louisiana by Prof. Richard Owen Trans. Acad. Sci., St. Louis, vol. 2, pp. 250-252, 1868. Abstract, Am. Jour. Sci., 2d Series, vol. 42, pp. 120-123, 1868. :t:Amer. Jour. Sci., 2d. ser., vol. 47, pp. 78-88, 1869; also Am. Assoc. Adv. Sci., Proc, vol. 17, pp. 327-340. 24 Geological Survey of Louisiana [Sect. Mississippi as far as Memphis and the Red to Shreveport. To account for the occurrence of the Orange Sand as seen in Louisiana the conclusion is reached that "in late Quaternary times the Gulf coast has suffered a depression to the extent of at least nine hundred feet (perhaps more), and during the Terrace epoch, a contrary motion of about half that amount." ' ' The features of the Grand Gulf group in Louisiana are almost absolutely identical with those prevailing in Mississippi." Hil- gard still maintains the necessity of a " temporary cutting off of the Mexican Gulf from the Atlantic to account for the existence of the Grand Gulf strata." He calls attention to the building stone, potter's clay, and a " fine white and exceedingly refrac- tory, semi-indurate white pipe-clay, occurring near the edge of the Vicksburg rocks in Catahoula parish." To the Vicksburg group, Hilgard refers practically all the marine Tertiary of the State. The only exception is the locality of the Zeuglodon on the Ouachita. For the lignitiferous beds in northern Louisiana he proposes the name of Mansfield group and correlates them with the lower portions of the Vick-sburg bluff. In discussing the " Salines of Northern Louisiana" Hilgard refers to the method of obtaining brine by sinking shallow wells 15 or 20 feet deep, sometimes by drilling deeper wells, even iioo feet and occasionally obtaining an artesian supply of brine. The records of these borings are unfortunate!}- lost. " But in one case at least the pile of borings, in others tradition testifies that calcareous or gypseous materials were met with all the wa^- down. This fact, coupled with the lithological character of the latter (which is foreign to all the Tertiary groups known to me) and the 'find' of several individuals of Exogyra costata and G?yphtza pitcheri in the rubbish of one pit, suggests that here we have not local Tertiary basins, but rather the peaks of a Cretaceous ridge, projecting through the lignitic Tertiary." In this report, as stated above, Hilgard describes the artesian wells of Calcasieu. They " are located on two small islands in the (fresh water) marsh which forms the head of the bayou Choupique," a small tributary of the Calcasieu river. At the time of Hilgard's visit the well being sunk by the I] Historical Review : Second Part 25 Kirkman's Well Depth 450 Thick- ness Ft. 354 96 Blue and yel- low clay some sand strata ■■-A ^^ Sandy pipe- clay, 4 ft. Louisiana Oil Co.'s Well Depth 160 333 343 583 443 543 690 Thick- ness Ft. 160 Materials Blue clay, sometimes with layers of sand soaked with petroleum 173 Loose sand and gravel, 138 to 153 ft. very pebbly; 153 to 173 ft. finer material Gray lami- nated clay ( "soapstone" 40 60 147 540 Blue, sandy, nodular lime- stone, with marine shells Petroleum and gas Soft, white, crystalline, crumbling limestone; tube driven through Pure crystalline sulphur Sulphur and gypsum, alternating About ^ sulphur. 5ft. Sulphur bed at 650 ft. 10-15 ft. bed at 680 ft. Pure gypsum Dense, gran- ular and coarsely crys- talline, gray- ish or white Formations Port Hudson Group Orange Sand Group Vicksburg Group Cretaceous Formation 26 Geological Survev of Louisiana [Sect. Louisiana Petroleum and Coal Oil Co. had reached a depth of 1,230 feet and Dr. Kirkman's well was 450 feet deep. Hilgard interprets and correlates the two as .shown on p. 25. Hilgard read before the Tro}^ meeting of the American Asso- ciation 1869, a paper "On the Geology of the Delta and the Mud-lumps of the Passes of the Mississippi.* Concerning the delta plain as a whole he believes that the river deposits cover it to but a " comparatively insignificant depth. 'f He has found the Orange sand beds in the Calcasieu well about 100 feet in thickness, lying below a 350 feet stratum of Port Hudson. The latter beds are found to resemble those in the New Orleans well, extending to a depth of 630 feet. Sir Charles Lyell's intima- tion that the beds were for the most part of a delta formation is again questioned and proven false by the microscopic and macroscopic fossils of marine origin found in them. The alluvium about New Orleans varies usuall}- from 31 to 56 feet in thickness beneath which or at the base of which is a stratum of mud in which combustible gas is frequently found. This is of indifferent quality as shown by analysis (p. 245). Accompanying this flow of gas are streams of water and mud making artificial mud-lumps of sometimes considerable dimen- sions (p. 368). The question of mud-lumps is taken up and figures illustrating their growth and decay are given (pp. 356- 368). Their origin is discussed at length (pp. 425-435) and analyses of waters given. In Hilgard's report on the material obtained from the New Orleans well (bored 1856) published in i8-jo,l he maintains that the distribution and kind of molluscan species identified show that at least the lower 510 feet of the well (630 feet deep) belongs to one and the same formation. It is not a delta deposit. It is the Port Hudson formation. A carefully drawn section of the well accompanies this report. Before the American Association in 187 1, Hilgard read a paper " On the Geological History of the Gulf of Mexico."* In this paper a Cretaceous " backbone " (p. 393) is said to pass through *See Am. Jour. Sci., vol. i, 1870, pp. 238-246, 356-368, 425-435- t Ibid p. 239. X Rept. Chief Eng., 1870, pp. 352-361. *Ain. Jour. Sci., vol. 2, 1871, pp. 391-404. I] Historical Review : Second Period 27 the State in a northerly and northwesterly direction and on either side there is a dipping of the strata away from the axis toward the Mississippi on the east side and westerly or southwesterly on the west side. The " Northern Lignitic " is correlated with the Buhrstone of the states east of the Mississippi (p. 394). He is led to make this mistake on account of supposing that the now well known Midway Eocene beds in west Tennesee lying immedi- ately upon the Cretaceous, were of Lower Claiborne age. Hence the intervening Lignitic beds should probably be of the same age. The Cretaceous backbone is held responsible for causing the extremely lignitic character of the formations of north Louisiana (p. 396). The barrenness of the Grand Gulf beds is attributed to some exclusion of the waters in which they were being deposited from the sea (p. 348). The calcareous concre- tions found near the base of this formation may have been derived from organic remains. The Port Hudson beds underlie the Mississippi alluvium up as far as Memphis, and the Red river as far as Shreveport (p. 401). The Smithsonian memoir by Hilgard on the "Geology of Lower Louisiana and the Rock salt of Petite Anse* published in 1872 is a more complete statement of the first article on the subject pub- lished in the American Journal of Science in 1869. He describes the Port Hudson section and gives a detailed description of each of the Five Islands. In this article he takes the view that the Five Islands are but the erosion-formed outliers of a Cretaceous ridge or backbone which traverses Louisiana from the northwest cor- ner in the direction of Vermillion ba^' ; the salt being of Creta- ceous rather than early Quaternary age. He thinks that at the beginning of Tertiarj- time the existence of the axis of elevation was marked merely by a number of disconnected islands. In later geological time the lower five outcrops were buried under deposits of Orange Sand and Port Hudson material, as indeed was the whole Mississippi valley, and in the re-excavation of the valley by the Mississippi river the material covering the Cretaceous nuceli was not eroded so much as the surrounding country, thus forming the islands. *Smith. Contributions, vol. 23, No. 248, 32 pp. 28 Geological Survey of Louisiana [Sect. Hilgard's Profile of Bluff at Sabinetown, Texas No. 14 Materials and Character Feet Formation Ferruginous sandstone, and conglomerate of pebbles with fragments of silicified wood . . 6 Drift 13 Ferruginous sand, of the usual Drift facias, with two or there ledges of ferruginotis sandstone 18 12 Yellow and variegated sand, with clay laminae interspersed 6 Mansfield Lignitic (Foot of Vicksburg Bluff) II Grey or brownish laminated clay wnth yellow (ochreous) cleavage planes, and a few sandy layers 25 ID Yellow and variegated sand, with clay bands at intervals of about twenty inches 30 9 Grey laminated clay with Selenite, and ferrugi- nous stratification lines at intervals of ten inches 12 8 Greenish ferruginous sand with clay laminse. 3 Jackson (Marine) 7 Ferruginous, concretionary sandstone, porous, fossiliferous 3 6 Solid blue sandy clay 3 5 Brown laminated clay I 4 Blue fossiliferous limestone, sandy, with Ros- tellaria velata '. 2 3 Greenish sand, alternating with clay laminae. . 6 2 Blue calcareous sandstone, fossiliferous 2 I Greenish sand, as far as visible 2 I] Historical Review : Second Period 29 In 1873 Hilgard published a "Supplementary and Final Report of a Geological Reconnaissance of the State of Louisiana. ' ' It is a large octavo phamphlet of 44 pages, and may be regarded as the most complete statement of the geology of the State heretofore published. No brief review can give an adequate idea of the contents of this work. It should be consulted by any and all who care to become familiar with the geology of the State. It gives soil analyses, topographic, geologic, vegetation and other characteristics of the regions traversed en route as out- lined in his previous report. On the preceding page Hilgard's section at Sabinetown, Tex. is given. " At the foot of the bluff, where at high stages of water it is difficult to find passage, it is lined with blocks of dark colored rock, tumbled from above. These are mostly derived from No. 7 of the section, a porous, concretionary, ferruginous sand- stone, with casts of fossils, now unrecognizable. There are besides, blocks of hard, limy sandstone or sandy limestone derived from No's. 2 and 4. The former is generally poor in fossils, the latter in places very rich, and the fossils well preserved, but very difficult to detach from the rock. Among them, a small variety of Rostellaria velala is the only fossil usually characterizing the Jackson group. But this, at the time of my visit, I failed to identify, and was inclined to consider the fauna found here more nearly related to the Vicksburg than to the Jackson group. But at a subsequent visit Prof. Hopkins found on a tributary entering the Sabine just above the ferry, a bed of shells bearing most distinctly the Jackson character. While it is thus proven that the lower (marine) portion of this profile is of the latter age, the upper (lignitic) part is thereby parallelized to the lower division of the Vicksburg bluff, to which it bears a close lithological resemblnace. And if we define the area actually underlaid here by the Vicksburg marine rocks proper, we cannot assign to it, on an average, a width greater than about three miles in a northwest and southeast direction." We are quite at a loss to know what shells Dr. Hopkins could have found here that would have a " most distinctly " Jackson character for they are purely upper Lignitic species as will be shown later on in this report. Moreover, Hilgard is still misled 30 Geological Survey of Louisiana [Sect. regarding the Vicksburg outcroppings by the little orbitolite specimens in the Lower Claiborne which he takes to be Orbitoides mantelli. The salt works in Northern Louisiana are well described, likewise the so-called marble and limestones. The Grand Gulf beds at Harrisonburg are well described. In the recapitulation he gives again the Calcasieu wells. In 1874, Hilgard published a " Note on Lignite Beds and Their Under-Clays " in the American Journal of Science.* In the course of this note he says : " The cause of this complete obliteration of spongy roots or spongy parts of roots is doubtless to be sought in the oxidizing influence of ferruginous solutions percolating from above, and the subsequent action of pressure on the yielding mass." * * * "That another phase of the same agencies has been instrumental in obliterating the teeming fauna of the Port Hudson beds, whose character can now be studied only in a few limited localities, I have already shown (Smith. Contr. Knowl., No. 248, p. 12). And there can be little doubt that the absolute dearth of organic remains which has thus far frustrated all vt\y attempts to gain a definite clue to the age of the Grand Gulf beds of the Gulf border, is largely due to the same cause, and not to the conversion of the Mexico Gulf into a dead sea during the Post-Eocene Tertiary period." In arguing against the aeolian origin of the Loess, Hilgard statesf that in Louisiana representative deposits are quite dis- tinctly stratified. In 1 88 1, Hilgard contributed an article on " the Later Tertiary of the Gulf of Mexico" to the American Journal of Science.! This article is inspired by the recent publication of the Coast Survey charf'Soundings in the Gulf of Mexico" and the observa- tions of Smith on the geology of Florida. On his map the northern edge of the Grand Gulf formation is made to curve around in Alabama and " run out " into the Gulf of Mexico at about the western extremity of Florida. It thus seems to have some relationship to the abrupt descent in *Vol. 7, pp. 208-210. fAm. Jour. Sci., vol. 18, 1879, p. 107. X^ol. 22, pp. 58-65, map. I] Historical Review : Second Period 31 the bottom of the Gulf not far to the east and southeast of Pensacola. The shelf along the northern coast of the Gulf, in case the bottom were raised 450 feet would be converted into a shallow water strip in which both fresh water and marine animals could have no safe footing. Add to this the partial closing of the Florida Straits and the Yucatan Channel and the whole Gulf would have become inhospitable for its marine denizens. The first report on the Mineral Resources of the United States published in 1883 contains an article by Dr. Hilgard on the Salines of Louisiana.* It contains a complete restatement of the information regarding the northern salines published in his earlier articles and much additional data on the mining opera- tions on Petite Anse. In the Report on Cotton Production in the United Statesf, part I, page iii, ei seg., Hilgard gives a brief summarj' of the geological features of the State, including however no new geo- logical facts. The soils of the State are discussed with care, and many exhaustive analyses of the same are given. In 1885 another article was contributed b}' Hilgard, entitled, " The Classification and Paleontology of the United States Ter- tiary Deposits. "J This article was inspired by the peculiar stratigraphy of O. Meyer and the answer b\' Heilprin. Hilgard does not believe in Meyer's stratigraph}'. On the other hand, he fully sympathizes with Meyer in considering many of Conrad's species as spurious or as varieties only ; states he gave up send- ing Conrad material because the latter would describe all varieties as species nova. Again and finally : "I doubt if there exists a finer opportunity for observing the evolution of marine species in Tertiar}^ times than is presented by the minutely differentiated formations of Mississippi and Louisiana." About simultaneously another article appeared from Hilgard's pen in the American Journal of Science, on The Old Tertiary of the Southwest. "§ He disposes of Meyer's ridiculous stratigraphy in trans-Mississippi deposits, and adds: "But, outside of the *Pp. 554-565- f47th Cong. 2d Sess., House Mis. Doc, No. 42, part 5, 1884. ^Science, vol. 6, p. 44. §Am. Jour. Sci., vol. 30, pp. 266-269. 32 Geological Survey of Louisiana [Sect. State of Mississippi, I can satisfy Dr. Meyer's postulate of 'seeing Vicksburg rocks actually superimposed upon the Jackson strata.' I have seen this in Louisiana on the Bayou Funne Louis, where I have stood on a ledge of Vicksburg limestone showing a south- ward dip and containing abundance of Orbitoides, Area missis- sippiensis and Pecten poiilso?ii, looking down upon a level prairie country in which the bones of the Zetiglodon have J^een plowed up." In 1887 Hilgard contributed to Science*, an article entitled, "The Equivalence in Time of American Marine and Intra-con- tinental Terranes." Herein the following significant passage occurs : ' ' The striking increase of the lignitiferous facies toward the northwestern border of the Gulf Tertiary area, culmi- nating in the appearance of bands of fresh-water limestone at Mansfield and northwestward ; the fan-like expanse in Arkansas and Louisiana of the older portion of the narrow bands formed by the marine stages in Mississippi and Alabama with a mani- fest northwestern trend of such deposits as are continuoslj^ traceable in northwestern Louisiana, while the later stages are abruptly deflected to the southwest, all points to a rapidl}' pro- gressing elevation of the axial Cretaceous trough that may or may not have completel}' . separated the interior from the gulf waters before the beginning of the Tertiary period." Hopkins. — In 1869 Dr. F. V. Hopkins made three geological trips in northern Louisiana and submitted his first annual report on the region covered late in the same year. In this report he reviewed the different geological formations occurring in the State from the oldest or Cretaceous to the most recent or allu- vial formation. His ideas of the stratigraphy of the State along a line "passing north through the Cretaceous outcrop in Winn and then turning a little southeast to intersect the St. Landry limestone, and the islands in the sea-marsh," is shown in the following figure : *VoL 9, p. 535> 1887. Historical Review : Second Period 33 ■ iRir ■.;.■".•.■■. ,■ -^-i--^-^.^^ iiiiiiiiiiiw MANSFIELD GROUPji^ '00 (!) CRETACEOUS t _l ^=^=0=52 Fig. I. — Transverse section of Louisiana. After Hopkins. The Cretaceous is said to rise to the surface in but few locali- ties. One is on Dugdamona bayou, S. 35, 12 N., 3 W. Another is in St. Landry about seven miles west of Chicot. Other Cretaceous rocks have been met with in wells, around Drake's salt-works, King's salt-works, and in the sulphur well at Calcasieu. The well section at Calcasieu he gives from information obtained from a Mr. Munu, as follows : Prairie Diluvium, i. 160 feet blue clay, layers of sand. Drift 2. 173 feet sand. Grand Gulf 3. 10 feet clay rock "soapstone." Vicksburg 4. 40 feet blue anthraconitic, limestone, fissured, f 5. 60 feet gray limestone. I 6. ICO feet pure crystalline sulphur. Cretaceous -{7. 137 feet gypsum, with sulphur. I 8. 10 feet sulphur. 1^9. 540 feet gypsum, gra)'ish blue. He is led to believe that : " The sulphur was formed by reduc- ing the gypsum with vegetable matter. The carbonic acid, olefiant gas and the marsh gas produced by the process, have each left the proof its presence, i. . . . .68 Vicinity of Many 68 Ft. fessup 6g Robeline 70 Cedar bluff. 71 Marthaville 71 Mansfield 72 Grand Caiie 73 Page Page Natchitoches 70 Grand Ecore 71 Stonewall 73 Shreveport 73 Lower Claiborne Stage Prei,iminary Remarks Areai, Distribution The map. ..74 Localities : (Sabine Parish) 74 Lo2v's creek, below Sabine- town 74 Lower Negreet 74 Simpkin'' s place 75 Leech neighboj-hood 76 Sotith of Many 76 (Natchitoches Parish) 76 Victoria mills 76 Provencal 77 Natchitoches 77 Black lake 77 Section 4, 11 N., 16 IV. ... . 77 (Winn Parish) 78 St. Maurice 78 Couley 79 Coochie brake 79 Winnjield 79 New Hope church 79 Sparta — Montgomery road, 24.th mile post 80 Vasherie bra7ich 80 (Grant Parish) 80 Georgetown 80 (Caldwell Parish) 80 Columbia 80 Lone Grave bluff 82 (Ouachita Parish) 82 Monroe 82 Calhoun 82 (Jackson Parish) 82 (Lincoln Parish) 82 Vining mills 82 Vienna 83 Redwine's spring 83 Niyie miles west of Ruston .... 83 (Bienville Parish) 83 Sect, j2, 14 N., 7 W 83 Sparta 84 Liberty Hill 84 Arcadia 84 Gibbsland 85 HammetV s branch 85 (Bossier Parish) 85 Coushatta bluff 85 Red land area 86 Bellevue 86 (Webster Parish) 87 Minden 87 Norther7i part of Parish 87 (Claiborne Parish) 88 Lisbon 88 Hay7iesville 88 Hom.er 88 (Union Parish) 89 D' Arbonne 89 Jackson Stage Distribution The map 89 LOCAUTIES : Bayou Toro 90 Tancock' s prairie 91 Rattan P. O go Tiillos 91 Mo7ilgomery 91 Olla 92 Ouachita river 92 OLIGOCENE ViCKSBURG Stage Distribution Roseficld 93 Grand Gulf Historical Origi7i of the TermGra7idGulf.g^ The Pascagoula formatio7i Study of the Grand Gulf {Miocene) 94 in Louisiana 94 Features of the Formation : Characteristics 95 Thickness 98 Distribution 96 Fossils 98 Age of the Grand Gulf Results of Work iii Alabama and Florida 98 LAFAYETTE Historical Origin of the Term Lafayette Features of the Formation in Louisiana Definite Features of the Deposits Distribution of the Gravels East of the Mississippi 10 1 Alo7ig the northern and southern borders of the Gra7id Gulf 102 Around Many aiid Sabinetown 102 The Black lake bayou gravel train 102 . St. Maurice and Montgomery 103 Ouachita river gravel train .\o\ hi N'n Union and Claiborne .io/\ Localities where gravels are Around the cretaceous outcrops \0/\ found in wells 104 Regions with no gravel Thickness of the deposits Conclusions QUATERNARY Classification Historical L,yell 107 Johnson 108 Hilgard 107 McGee 108 Table of Louisiana Quaternary Formations River development 109 Coastal development 109 Development and Characteristics of the Louisi- ana Quaternary Formations Manner of Formation Natural periods in the Qua- Period of elevation no teriiary of Louisiana 109 Present period of subsidence . no First period of subsidence . . . 109 The Basal Gravel Characteristics and development in The Port Hudson Origin of term in A real distribution and topo- General characteristics 112 graphical features 113 Synonymy 112 Thickness of the Port Hud so7i. 114 Fossils 114 The Lcess and Yellow Loam Origin of tej'ms 115 Origin of the lcess 116 General characteristics of the The yellow loatn 116 loess 116 Distribution 117 The Alluvium and Recent Coastal Formations Recent coastal formations . ...117 The Alluvium 118 D Quaternary Phenomena other than Erosion AND Deposition Local Crustai. Movements The Five Islands ii 8 The Mud Lumps Description 119 Theories of origin 119 DIVISION II. ECONOMIC GEOLOGY Important Products Salt Drake' s salt works 121 Bistineau salt works 124. Ray burn' s salt works 122 Sabi^ie parish salt works. . . 124 King' s salt works 123 Other salt springs 124 Price' s salt works 123 Five Islands 125 Conclusions , 125 Sulphur Sulphur City, Calcasieu parish 126 Clays Geiieral statement 127 Catahoula parish 128 Verno7i parish 129 Sandstone Varieties 129 Harrisonburg 1 30 Buyout Toro 129 Petite Ansc 1 30 Boyce 130 Limestones Cretaceous limestones 130 Tertiary limestones concretions 131 Gravel Unimportant Mineral Products Iron Ores Lignite Dolet hills 135 Majisfield 136 Stone coal bluff .Sabine river. 135 Shreveport 136 Many 1 30 Sec. 11, 18 N. , S W. 1 36 Lead and Zinc Ores Mart. Gypsum Petroi,eum and Gas Lake Charles 137 Shreveport 138 Belle Isle 138 Negreet bayou 138 Breaux B?-idge 138 CRETACEOUS SERIES Ripley Stage Preliminary Remarks la our historic review we have called attention to the fact that Judge Bvy, early in this century mentioned the occurrence of Cretaceous fossils on the Ouachita river ( see p. 1 6 ) . Morton ( see p. 17 ) soon followed with references to other localities of this formation in the State, namely between Alexandria and Natchitoches. But there is every reason to believe that these early references were based on faultj^ evidence, the former on improper identifica- tions of fossil remains, the latter on merelithologic resemblances. Hilgard's references to two characteristic Cretaceous species found in dumps from salt wells in northern Louisiana have fre- quently been pointed to as the first satisfactor}' proofs of the Cretaceous series in Louisiana. But when it is seen by his Supple- mentary and Final Report (p. 28) that it is King's salt works that yielded these fossils and that the Gryphira pitchc?'i is really Ostrea pulaskensis a characteristic Midway Eocene species ; and the character of the material in which the}- are embedded is precisely that of the lower Eocene beds near Prairie bluff and Snow hill, x\labama, we are led to surmise that the E. cosiata was in reality something else or w^as brought up from some distance below the surface or from some altogether different locality. We must therefore include King's salt w^orks under the next stage, nameh', the Midway Eocene. Localities Raylnirn s saltivorks. — Mr. Lerch's report for 1892 (p. 13) this locality is described as in Section 24, 15 N., 5 W., about 10 miles southeast of Bienville. An ideal section of the rocks at this locality is given which, b}* the way is considerably at variance nj General Geology : Cretaceous 53 with Veatch's notes on the same region (see Fig. 2) ; but he mentions the occurrence here of well-preserved Exooyra costata. -wm ° ° W_s-. \ Cretaceous Lower g^jj. ^^jj^ Old Salt Claiborne Furnaces Fig. 2. — Sketch Map of Rayburn's Salt Works 54 Geological Survey of Louisiana [Sect. The locality given by Hilgard and Lerch seems to be in error. The junior author has carefully gone over the deeds in the pos- session of Mr. Whitlow, the present owner of the place, in which the land is described as Sec. 31, 15 N., 5 W. The old salt furnaces and wells cover about forty acres of a little circular valley' which lies around and a little west of the center of that Section. The hills which surround the valley slope very gentl}^ down from an elevation of sixty feet, which they attain over a mile from the old works. The southern end of the valley is quite swampy, and during heavy rains is flooded to depth of two or three feet. The little outlet creek, Fousti creek, has its origin in the lower end of this swamp. Around the edge of the valley are numerous circular mounds about sixty feet in diameter and three to four feet high. They are of the same type as the little mounds which are so common in different parts of Louisiana. The old dump heaps around the wells, the latter from fifteen to twenty feet deep, show large quantities of varioush- colored quartz and chert gravels. Fragments of dark gray and yel- low fissured crystalline limestone, and of white or bluish white masses of gypsum, are quite abundant in some of the old dumps. The hills surrounding the old lick are composed almost entirely of gray sand with small iron concretions. On the area mapped, but three places were seen which showed anj^thing harder than sand. Just east of the wells, from five to eight feet above them, is a little patch of black prairie land covered with small hawthorn bushes. On the surface of the prairie numerous specimens of large Gryplura vesicularis and a single valve of Exogyra costata were found. It seems queer, from the abundance of the former species and the comparative scarcity of the latter, that the only large Ostrea- like shell mentioned b}' Lerch occurs at this locality in Exogyra costata. Immediately below the black soil is a la^-er of very soft white, chalk -like limestone. It is from this that the large shells have been derived. It is filled with finely preserved Cretaceous fossils. The following is a partial list of the species found here (mainly Stanton's identifications): n] General Geology : Cretaceous 55 Exogyra costata, Inoceramtis barabina ? GrypJuFa vesicularis, Legumen planulatum, Osirea pltanosa, Linearia 7neiastriaia, Ostrea larva, Avellana bullata, Peden burlingtonensis , Baculites anceps, Neithea quinquecosta, Heteroceras, Crassatella vadosa, Ptychoceras. A second outcrop containing poor Cretaceous fossils was seen north of the old wells. Near the southwestern part of the area shown in the map the sandy land is replaced b}- stiff clay land, identical with the stiff Lower Claiborne land further north. The iron concretions which occur in places throughout the clay contain Vejiericardia and a few imperfectly preserved Gastropoda. Section j2, i^ N., 7 W. — Found by recent investigation to belong to the Lower Claiborne stage, which see. Head of Lake Bistineau. — The old works here, Hopkins has mapped as Cretaceous on account of the supposed connection between the salt beds and the Cretaceous series ; covered, except at low stages of water. Recentl)- proven Cretaceous by Vetach. Price' s lick. — This is listed by Hopkins and Lerch as a Creta- ceous outcrop simply because of the presence here of strong saline springs. Location : S. 25, 13 N., 5 W. '' Old salt works.'' — This is represented on Hopkins' map as being in S. 35, 13 N., 6 W. Nothing definite is known of these works. Drake's salt works. — Section 21, 12 N., 5 W. The Licks, according to Hilgard, extend along Saline bayou for one and one-half miles, "At their northern end, on the east bank, a number of artesian wells have been bored ; one, a thousand and eleven feet deep, and said to have been sunk in uniform lime- stone rock all the way, spouts a constant stream of from eighteen to twenty gallons of salt-water per minute." * * * * " Here, as elsewhere, many pits were dug during the war, fifteen to eigteen feet deep. All these struck the laminated clay, or " soap- stone ;" but in the rubbish of one I found large fragments of a very cr^-stalline, j^ellowish limestone, horizontally banded with gray ; evidently the same as that at King's and Drake's." There can be no doubt that much of the limestone passed 56 Geological Survey of Louisiana [Sect. through in the deep well was of Cretaceous origin. Doubtless, too, some of the shallower wells reached the same formation ; but as yet, no positive proofs of the age of the various strata are at hand. Wmnfield limestone : SS. /p and jo, ii N.,j IV. (according to Lerch). — Perhaps there is no locality in northern Louisiana that can excel this in features of interest, for the geologist and layman alike. Nor is it a matter of wonder that great local inter- est should be manifest in this high mass of dislocated, faulted, folded rocks, showing here a mere confused mass of angular boulders, there a vertical cliff" of 30 feet with rocks of all shapes and sizes piled up in a sloping talus at its base. The "Tower rock" or "Chimney" is well shown on PI. i. The rugged, fractured character of the cliff at this place is also well illustrated. Below the sloping talus, to the left of the picture is a small pond occupying a central or crater -like area of the upheaval that brought up these rocks from beneath the Tertiary strata. The number, relative importance and positions of the various limestone outcrops of this region are shown on the accompany- ing topographic sketch, (Fig. 3) made by this survey early in the season. On the western end of the high bluff in the center of the map the ledges seem to dip in a northerly direction. But farther east they dip eastward. Other outcrops to the left of the center of the map have a northerly or rather northwesterlj^ dip of from 30° to 45.° The chimney seems to be composed of nearly horizontal layers. The position of the other outcrops together with what dips have been ascertained seem to indicate that there is here an irregular anticlinal fold extending in a northeast and southwest direction ; that the greatest energy in the upheaving force took effect not far east of the "chimney," and about in the present Bayou channel ; that the axis there divided and the upheaval of the eastern outcrop was one result and the outcrops west of the Bayou to the north was another. The general trend of the various outcrops is towards the Coochie brake west of Atlanta, discussed below. Hilgard says briefly regarding the dislocations here shown : 11] General Geology : Cretaceous 57 "It evident that subsidences and consequent dislocations fre- quently occur in the mass ; and large fragments frequently tumble down." Hopkins' section (see p. 33 of this report) shows his idea of the relation of the Eocene and Cretaceous. — E- VHi Cretaceous Outcrops Fig. 3. — Sketch of Winfield '\ marble''' quarry and sitrrotaidings. This map embraces one square mile. Elevations are denoted by contour intervals of 20 feet, commencing with o at the base of the eastern Bluff. Johnson has indicated that the Cretaceous limestone, Tertiary limestone (which he improperly calls Jackson) and the Orange sands above, are each unconformable in their bedding to all the other layers. lyerch (p. 72, 2d report), says definitely that "at the close of the Me.sozoic time enormous plutonic forces convulsed, fractured, 58 Geological Survey of Louisiana [Sect. faulted and folded the Cretaceous strata, throwing up mountain chains of vast extent, and raising them far above the waters of the gulf." "If we could remove the covering mantle of Tertiary and drift, we would yet see the chains and peaks of limestone ranges formed at the close of the middle age of our planet, altered somewhat by later erosion and denudation. ' ' He believes there was no interval of a land period between the Cretaceous and Eocene in this State. Vaughan * argues that there was a time interval between the close of the Cretaceous and the beginning of the Eocene, and adds : " Furthermore, the Cretaceous at the Winn parish marble quarry is almost horizontal, the limestone rising as a butte-like mass into the Eocene. If there had been a mountain chain, as Dr. Lerch maintains, with the Eocene deposited immediately thereafter, before erosion had degraded the limestone, the Cre- taceous rock at the place under discussion should represent either a dome or anticline, but such is not the case. In the mind of the author the most logical explanation of the relation of the Cretaceous to the Eocene is that a land period followed the close of the deposition of the rocks belonging to the former series." Vaughan is doubtless right so far as his last statement is con- cerned. Nowhere along the Atlantic or Gulf slope are we aware that the Eocene follows the Cretaceous without a marked strati- graphic break. But he is wrong in saying that domes and anticlines are not here represented. In fact both are splendidly exhibited. Nothing could be more apparent than the dome-like structure of the easternmost bluff whose western end shows a northern dip, which but a few yards eastward swings around eastward and finally becomes due east. To be sure it is only the N. E. ^ of the dome that is represented by this bluff. In some instances the rocks are so faulted, fractured and fissured that no general dips can be ascertained ; but we are strongly inclined to believe the huge masses of Lower Claiborne limestone indicated to the north — northwest of the Cretaceous escarpments are quite highly inclined to the north. It then follows that the time of upheavel of these limestone deposits was since the Lower Claiborne time. * Amer. Geol. Vol. 15, p. 208, 1895. n] General Geology : Cretaceous 59 The character of the Cretaceous limestone here exposed is such as to render it almost useless as a building or ornamental stone, but it can be used to advantage for making lime. It is full of cracks, pockets and joints ; is highh' crystalline and shows whitish and bluish bands of various shades of color. So far no fossils have been observed in these crystalline limestone ledges. The Lower Claiborne limestone is of a yellowish or reddish white color, far less crystalline and very fossiliferous. Limesto?ie tiear Coochie brake. — The illustration herewith given, Fig. 4. — Sketch map of vicinity of limestone outcrop near Coochie brake. The contour intervals are here 20 feet as usual. The little rise to the extreme right ^narked "^ 40^^ is shown in a correspo?iding position on PI. 2. PI. 2, was taken just south of the limestone outcrop in the direction indicated by the large arrow (see Fig. 4). Here there is a northwestern quarter of a dome-like upheaval well exposed. To the east is what appears to be a less marked, or lower structure of similar nature still hidden beneath the surface soil. Their location and general relations to each other are likewise shown on the sketch-map, Fig. 4. This limestone is more arenaceous or sand}' in appearance than that at Winnfield ; but is of a most excellent quality for building purposes. Its beauty as building material is, however, 6o Geological Survey oi< Louisiana [Sect. greatly marred by the nodules of pyrite scattered throughout its mass, causing streaks and blotches of iron oxide over its exposed surfaces. Its quantity is doubtless sufficient for any demand that is liable to be made on such material for many years to come. The peculiarity of this limestone outcrop in the midst of Ter- tiary sands and clays has naturally aroused local curiosity. The glittering appearance of the freshly broken pyrite nodules has doubtless been at the bottom of the vast majority of statements made concerning the mineral wealth of this region. Vaughan* has made the following pointed statement regarding this exposure: "On sections 31 and 32, T. loN., R. 4W., near Atlanta in Winn parish, there outcrops a hard, blue limestone, which is traversed by minute fissures. In these fissures a small amount of gold is found." This must have been a near shore deposit, for it contains the impressions of dicotyledonous leaves, reminding one somewhat of the Dakota sandstone. The age of the limestone is not known to a certainty. As pointed out above it is quite different in lithological character from the Winnfield marble ; but since the present position of the outcrop is due to a similar, if not the same orographic movement that brought up the Winnfield beds; in fact, both seem to be on the same line of weakness, N. E., S. W., we are led to regard all as of Cretaceous ages as else- where explained. Coochie brake seemingly owes its origin to the same disloca- tion of the strata that brought up these limestone beds from below. It appears to rest upon the down-throw side of the fault-line that fractured these dome-like structures along their major axes. In case the weather were wet, a pond of water, very analogously located would be formed along the south side of the Winnfield outcrops, where in dry seasons only a stream is formed which has subterranean connections with Bayou Sonnel. The origin of Coochie brake or Coochie lake as it is sometimes called, has little in common with the origin of the larger lakes found close along the Red river channel. This lake is but a few * U. S. GeoL vSurvey, BulL 142, p. 12, 1896. II] General Geology : Cretaceous 6i feet in depth as proven by the cj^press knees everywhere present, and by the fact that wading is possible well out to the middle. The author took the photograph shown as Plate 3, by wading out about ys mile where the water was scarcely 3 feet deep. The following detailed account of the timber contained in this brake has been kindly furnished by Mr. Ferguson, who person- ally surveyed the brake and made the estimates. Brake contain somewhat over 700 acres ; with 87,920,000 feet of cypress, 29,000,000 feet of gum, 14,000,000 feet of tupelo gum, 30,000 feet of long leaf pine. Cedar lick. — Hilgard* says of this locality: "About seven miles southeast from this limestone hill [Winnfield marble], there is another salt lick called Cedar lick (from cedars growing there) ; it is several acres in extent, and there is on it a steadily flowing brine spring of pure taste and considerable strength. It can hardly be doubted that here, also, the Cretaceous rock underlies at a moderate depth." Rapides Parish. — Johnson mentions a Cretaceous outcrop on N. E. ^ S. 26, 6 N., 4 W. in Rapides parish. We have not yet had time to investigate this locality. Bayou Chicot limestone. — Two outcrops are included under this heading. They are located in S. 35, 3 S. , i W. , about eight miles southwest of Bayou Chicot P. O. They have been visited and favorably reported upon by Hopkins ; unfavorably by Clendenin. One shows an exposure of eight feet high and fiftj^ feet wide. This was made in procuring limestone for burning, and the ruined kilns can still be seen. The dip of the rocks is 22°, S. 70° W. The second is exposed in the bottom of a pit about 350 yards southeast of the first mentioned outcrop ; shows a dip of 33°, S. 65° w. The limestone is here of a much darker color on an average than at the more northern outcrops. Some fragments, however, * Sup. and Final Report Geol. Reconn.. La., p. 32., 1873. f House Ex. Doc. 50 Cong. ist. Sess. No. 195, p. 23., r888. 62 GeoloCxICAl Survey of Louisiana [Sect. show a tendency to the white and blue banded structure so characteristic of the Winnfield layers. Were it not for the excessive dip of these localities, carrying the beds below at a rapid rate, this limestone would doubtless be quarried extensively. The Five Islands. — For information concerning the supposed Cretaceous layers in these islands, see special paper devoted to their geology. Calcasieu Well Section. — As already shown on p. 25, the crys- talline limestone, sulphur and gypsum beds in the Louisiana Oil Co.'s well on the west fork of Calcasieu river have been referred to the Cretaceous series. (See special topic Sulphur.) CONCI^USIONS Much has been said in geological reports on the State of Louisiana about the Cretaceous "backbone" which extends in a ridge northwest of the Five Islands to the Salines of Bienville parish. This Cretaceous ridge was supposed to connect onto a fictitious southern deflection of the same series in Arkansas as laid down on Marcou's geological map of the United States. Our observations go to show that whatever folding and faulting has been the cause of bringing the underlying Cretaceous strata to day, has been in the northeast-southwest direction, roughly parallel in fact to the northwestern shore line of the old Missis- sippi embayment in Eocene Tertiary time. The shallow depth at which rocks supposed to be of this series have been struck in the Calcasieu wells (380 ft.); the salines at the mouth of Bayou Negreet and to the north ; the Midway beds a few miles to the northeast of Many ; the great depth of the Shreveport well (1,100 ft.) with no record of Midway or Creta- ceous limestones though nearly in line with the so-called axis or "back-bone"; the various dips observed in the limestones at various exposures with but one exception — the St. Landry out- crops — all indicate northeast-southwest local folds parallel to old shore lines rather than a mountain chain at right angles to the same, or in a northwest-southeast direction. EOCENE SERIES Midway Stage IvOCAl,lTlES Rocky Spring church. — On the road from Marthaville to Many near Rocky Spring church (N. E. X Sec. 24, 8 N., i] W,, on the Ranes' place) a very impure limestone is met with in the bed and left bank of a small stream. Impure as it is, this lime- stone is said to have been used for lime in the construction of Ft. Jessup. To the westward, perhaps one-half mile on higher ground, a well is said to have passed through a bed containing shells in abundance. Another well to the north one-fourth mile, encountered the same stratum. Calcareous spots (black lands) are common in the near-by fields. One mile to the east a yel- lowish gray concretionary boulder was found in a bank by the roadside (Marthaville-Fort Jessup road), containing cross-sec- tions of the shell of Cardium ttwmeyi (^? ') . Still further east- ward, about one mile, ferruginous layers by the roadside show casts of lyignitic species. This is doubtless the locality referred to by Hopkins in his second annual report (p. 10), as at Mr. Dillard's place, five miles north of Ft. Jessup. He says it consists almost entirely of the remains of Ostrea georgiaiia, an immense oyster found only in the latest Jackson beds. He was therefore quite mistaken as regards the species of oyster here represented as well as in horizon. King' s salt works. — We can scarcely doubt, from the state- ments of Hilgard, that here are to be found Cretaceous beds not far beneath the surface. As early as 1869* he reports the find- ing of GyphcBa pitcheri and Exogyra costata in some old well bor- ings in the " Salines of North Louisiana," though no particular well or locality is mentioned. In his final report, however, * Am. Journal Sci. vol 48, p. 342. 64 Geological Survey of Louisiana [Sect. he definitely states that these characteristic fossils came from King's salt works, S. 35, 15 N., 8 W. Vaughan* has recently shown that Hilgard was mistaken in his identification G. pitcheri, it being a Comanche stage fossil, while the deposits with E. costata must be Upper Cretaceous. Yet Vaughan did not suggest what Hilgard's G. pitcheri really was. We know now from the collections made at the place by Veatch that this species is no other than O. p2{laske?isis, Har., a typical Midway Eocene species. Hilgard properly describes the rocks from which these shells were obtained as a soft gra}-, calcareous mass. In fact it is most strikingly similar to the basal Eocene beds around Prairie bluff, and Snow hill, Alabama. He remarks : " A few hundred yards northward of the lick, there is a dug well 20 feet deep in which a similar rock was struck at 5 feet, which became harder as the depth increased, and had to be blasted. The rock now lying near the well is a rather hard, crystalline limestone, full of debris of shells ; a great many perfect ones were found in digging ; one described to me must have been a /a/z/ra. No salt water w^as obtained in this well." Other localities. — That the above two were the only places in Louisian? -vhere Midway or Lowest ICocene beds outcrop, seems very improbable. Black land areas reported from Mansfield westward ma}^ possibly owe their origin to the calcareousness of this stage. Another place that must be looked up shortly is on the Soda lake where CoUinsf reports " Natdilus dekayi'' half- way between Albany and Henderson's mills. LiGNiTic Stage Preliminary Remarks The presence of this stage west of the Mississippi has been suspected ever since its differentiation, and its true relationships to the other Eocene stages was worked out along the river courses in Alabama. *Amer. GeoL vol. 15, p. 207. t43dCon., 1st sess. Ho. Ex. Doc. voL 2, pt. 2, p. 661, iSyj. 19 Hovd -vl 'HHvaa aiHDOoo Ni naaiMix 66i,'l 'iHOdaH 'VXVISIilOl AO AHAHnS TVDIOO-IOHO •^•^-^"•^^-"--^^ «^^-^-^^^^^^^^<-^'«»^^^ rVKor.ocitAT. Si;kvi;v on Loimsiana, Re.roRT, 1899 I'l.ATK 4 Topograthic Sketch M'P'f Many ToH.nsMp pv A. C. \EAJcb II] General Geology : Lignitic Eocene 65 Certain sandy and cla3'ey layers containing more or less lig- nitic matter, but without animal fossil remains, lying geograph- ically between the Midwaj' and Lower Claiborne outcrops in Texas and Arkansas, have been provisionally referred to this stage. Lines of demarcation, however, between this and higher Eocene stages, have been difficult to locate insomuch as materials lithologically similar occur in this and man}' of the higher beds. We have already seen how in Louisiana these beds have been given a special name, "the Mansfield Group," and correlated with the beds at the base of the Vicksburg blufi", then with the Jackson stage, and afterwards with some pre-Jackson horizon. Definite proof of the position these beds occupy was first given in Bulletins of American Paleontology, vol. 2, p. 202, 1897. The locality there discussed, — Sabinetown, Tex., — has been revisited by members of this survey' and now can be discussed in detail. Areal Distribution The Map. — The area represented on the map as belonging to this stage may have its boundaries somewhat modified by subse- quent investigation. But it certainly repsesents the truth with a fair degree of accuracy'. To this survey belongs the credit of identifj'ing or proving the existence of the Lower Lignitic, in this State hy means of fossil remains, and being able to sa}- pos- itively that there is a southern peninsula-like extension of this stage in Louisiana between the Red and Sabine rivers. Localities Pendleton. — Along the Sabine river the best outcrops are seen on the Texas side. Yet since they throw such a vast amount of light on the geology of Louisiana, — for the same beds must occur east of the river though covered by detritus, — it seems highly desirable to insert them here in detail form. The following section may be seen one- fourth mile above the ferry, just above the mouth of a small bayou. 9. Light gray to brownish laminated clay 7.5 ft. 8. Ledge of impure limestone concretions 2.5 ft. 7. Greenish brown and light blue clayey sand, with iron concretions and fossils 4- 5 ft. 66 Geological Survey of Louisiana [Sect. 6. Blue joint clay, fossiliferous 2.5 ft. 5. lyimestons boulders, fossiliferous, in dark gray sand . i ft. 4. Dark gray sand 2 ft, 3. Stratified lignitic clay i ft. 2. Yellow and gray sand 5 ft. 1. Wav}', alternate layers of blue sand and clay 6 ft. Water-level. The dip is here to the westward about i to 50. The main Pendleton bluff, just above the ferry, is about as follows : 5. Red sand 15 — 20 ft. 4. Light gray and brown laminate clay 5 — 15 ft. 3 Ledge of limestone and sandstone boulders 2 — 3 ft. 2. Light blue sandy clay, with fossils and iron con- cretions 5 ft. 1. Wavy alternate layers of dark sand and clay. ... 8 ft. Fossils are numerous at each of these exposures, but are some- what better preserved in the first mentioned section. They include (as may be seen by referring to the paleontology of the Lignitic Stage) such typical lower Eocene species as Levifusus siipraplaiius , Buccina7iops ellipticum, T2irritella prcrcinda, Natica aperia, N. alabamiensis, Solarium bellense and Pleurotoma silicata, leaving no doubt as to the horizon they represent in the Alabama .section. Stone coal bluff. — Down the river about half way from Pendleton to Sabinetown, but on the Louisiana side there is a 3 ft. ledge of lignite cropping out near water level. It is over- laid by gray sands of recent river origin. (See under Lignite, Economic Geology.) Salt licks. — About ^ mile northeast of this lignite outcrop, are extensive salt licks where formerly large quantities of salt were made. (See further under Economic Geol. — Salt.) Slaughter's creek lignite — This is located on S. W. %, S. 35, 6 N., 13 W. The beds associated with the lignite are as follows : 4. Reddish sandy surface loam i ft. 3. Alternate laminate of chocolate clay and gray sand. . . .9 ft. 2. Lignite 4 ft. I . Gray clay to water level i ft. n] General Geology : Lignitic Eocene 67 (See further under Econ. Geol. — Lignite.) Sabinetow7i. — A short distance below the ferry on the Texas side of the Sabine there is a most interesting section, not only for the light that it sheds on the geology of west Louisiana, but also for the various horizons to which its beds have been referred. (See under Hilgard, Historic review.) Putting aside the past, we proceed at once to a detailed description of this classic locality. This bluff is from 115 to 120 feet high, counting from the surface of the river at a medium stage of water. It is located on a bend of the river where the latter pursues a nearly east-west direction. Though the dip is locally very considerable here as shown in little side gorges often J^ south, it appears slight along the bluff as a whole, for the direction of the latter is nearly on the line of strike. The main features of the various component strata are as follows : 8. Sands and ferruginous conglomerates 9-16 ft. 7. Ferruginous sandstone i ft. 6. Eignitic clay 15 ft. 5. Yellow sand 25 ft. 4. More or less alternating shaly lignitic clay and sand. The latter weathering yellowish ; the shaly clay sometimes light brown or pinkish 40 ft. 3. More or less clayey sand, often greenish and fossilifer- ous in concretions ; with a hard layer above 15 ft. 2. Fossiliferous blue sand with concretions 6 ft. I. Brittle, shaly, drab clay 2 ft. We have only to glance at the fossils to be impressed with the almost perfect likeness they bear to the Woods bluff beds in Alabama. Some have already been figures in Bulletins of American Paleontology and others may be found elsewhere in this report. (See Paleontology the Lignite stage.) The best fossils are found in the greenish sandy layer at the west end of bluff, just east of where a little stream empties into the river. Low' s creek. — One and one-half mile to the south of Sabine- town bluff in the bed of Low's creek at the ford, Lower Claiborne fossils are found. But beneath the same in what is presumably Lignitic material, a vast number of Pedens cornuus occur. 68 Geological Survey of Louisiana [Sect. The beds at the water-mill are of this lower layer. They are replete with oolitic iron ore, greenish when freshly exposed, red- dish when weathered. Vicinity of Negrect P.O. — In stream beds about Negreet a bluish, sandy, lignitic clay is now and then to be seen. But the most prominent exposures, as at the church and cross-roads N. W. of the P.O., show beds of sand with ferruginous, shaly partings. Mr. Harvy Gandey's place shows in several localities the very sandy layers just mentioned, together with large ferru- ginous chunks, or rock fragments, reddish for the most part, but with pockets of yellowish limonite. In digging a well on his place some 20 years ago, Mr. G. found fossil shells in abun- dance. This fact should be borne in mind by residents of this community, for the very sand}' series of the uplands could be improved by the application of the calcareous material obtained from these fossiliferous marh' deposits. It is to be regretted-that the survey has not yet obtained the analyses of soils taken from the bottom lands of this place. They must be reserved for the next ^^ear's report. The pecul- iarity which they should show, however, is the nature of the saline efflorescence wdiich oozes up from below, making in con- junction with the sand that accompanies them the regular low hillocks or mounds, that characterize many of the fiat regions of this and other southern states. On Mr. Henderson's place, 4 miles N. N. E- of Mr. Gaudy's, on the Many-Sabinetown road, marine shells are said to have been found in considerable quantities. Vicinity of Many. — The accompanying map shows the topog- raphy of the region well, viz.: broad, flat bottoms, and steepl)' sloping, much carved uplands. The valle}-s seem to owe their shape more to the filling up of a young V-shaped valley result- ing from a change in the position of the base level than by the excavating action of the present streams. Along the stream beds, bluish or blackish sandy clays now and then appear ; but the commoner beds exposed are clays and light colored sands. At one place, in the bank of Tar river at the Devil's backbone, a thin bed of lignite occurs. Here and there are light yellowish, concretionary calcareous boulders, containing sometimes leaves, II] General Geology : IvIgnitic Eocene 69 as seen in those thrown out in the cuts of the R. R., perhaps 1% miles southeast of Many, sometimes marine shells (generally Ve7iericardia planicosta) as seen in the boulders near Tar river, south of Many and in others from near Ft. Jessup. Lagoon and off-shore conditions evidently alternated geograph- ically and stratigraphically during the deposition of these beds. Layers of lignite are reported from various places in this vicinity. Casts of fossils are fairly abundant in the dark sandy mica- ceous clay on La Nana bayou, as it crosses the 29-30 section line. This material is strangely similar to the lower Eocene beds of Maryland and Virginia. The most characteristic fossil species are : Turritella mortoni, I ^olutilithcs peirosiis, Pleurotoma siphus, Astarte smithvellensis, var. Venericardia plaiiecosta, Pseu- doliva, sp. (See further under Paleontology, Lignitic Stage.) In the little ravines or washouts near the Many school-house castsof several lignitic species of mollusca are found. They are embedded in indurate ferruginous, crust-like layers of argilla- ceous concretions. Similar beds were noticed for a mile or more to the southeast of this locality. Such casts are also abundant in the S. E, % of the S. W, % of Sec. 13 near Jerusalem Church. Just across the township line in Sec. 19, 7 N., 10 W. shells have been found in a well. Ft. Jessup. — In this locality many yellowish concretionary boulders are to be seen. In fact the rocks that were used in con- structing the Fort were of this character. We observed none con- taining plant remains. They were either barren or with traces of molluscan life. A fragment picked up at the old Fort contained a perfect mass of a small univalves. Another fragment found nearby contained many ]^encricardia planicosta. Just to the east of the village Rocky creek sets in and extends nearly by the Williams place. Its banks are high and precipitous and afford the best view of the geology of the region yet seen. The characteristic or predominating material is dark clayey sand or sandy clay containing shining particles of mica and quartz. On the Williams place perhaps one mile east of the Fort, several fossiliferous boulders were seen. In the banks of a yo Geological Survey of Louisiana [Sect. stream, several imprints of marine fossils were found, including Turritella hiinierosa, and what seem to be fragments of Volutili- thes petrosiis and small fusoid forms. Going eastward along the road to Robeline one sees several hill-slopes with light sands and clays, the latter apparently of a good grade for pottery, and ledges of rock (3^ miles from Robe- line, on what is called Kirkam or Rock Chimney hill), remark- able for the size of the lenticular or irregular shape concretions they contain. Robelme. — A good potters' clay has been worked 2^ miles east of Robeline on the Carter place. It is yellowish and quite sandy, but is very hard and tough to pick. Some 6,000 flower- pots and many jugs were made here a few years ago. There is a considerable difference in the amount of sandy material inter- mixed in the various clays seen outcropping in this vicinity and the so-called sassafras clays have been extensively used for bricks without the admixture of sands or clays from other strata. Mr. Ponder S. Carter has charge of this estate at present. He very kindly donated to the Survey a flower-pot and jug made from these clays. Along the railroad track towards Victoria mills numerous cuts are seen exhibiting the Lignitic clays to good advantage. Lerch has given figures of two of these in his 2d report on the hills of N. Louisiana (p. 76). One shows two seams of Lignite. This Survey (1899), found numerous traces of marine mollusks in some of these layers. Near Victoria Mills the Lignitic strata pass beneath those of Lower Claiborne age. Natchitoches. — The best display of Lignitic strata in this vicinity is at Grand Ecore. But beds of a similar character crop out on Cane river just north of the town. They are there over- laid by fossiliferous Claiborne deposits. (For illustration of this bluff, see special report on Natchito- ches area.) The larger part of the upland of this township is underlaid by sandy and clayey deposits of the Lignitic stage. There appears to be far less calcareous matter in these deposits than was observed in those of the same age about Many. (See further under special article on Natchitoches area.) II] General Geology: Lignitic Eocene 71 Grand Ecore. — Hopkins visited this section as early as 1869 and published a section of its beds in his first annual, 1870, p. 86. The beds with their estimated thicknesses as they appear just above the landing, or terminus of the R. R. track are as follows : 10. Sand with quartz pebbles 10 ft. 9. Orange-colored sand, with white clay-ball concretions. 10 ft. 8. Yellow sand 2 ft. 7. Colored (greenish) clays 3 ft. 6. Finely laminated, light, yellowish, clayey sand 18 ft. 5. Brown, black-banded, lignitic sand 9 ft. 4. Black and gray sand and sandy clay 6 ft. 3. Lignite 20 in. 2. Black clay shale 2 ft. I. Grayish sand or sandy clay 5 ft. Water level. The face of the bluff farther upstream, as well as the top of the low bluffs below, show many large light yellowish con- cretions. Cedar bluff. — Nearly east of Grand Ecore, on the Saline bayou, not far to the north of Congo, P. O., on the land of Mr. John Kieffer is an escarpment commonly known as Cedar bluff, which seems to show practically the same series of lignitic sands as have just been enumerated under Grand Ecore. The bed of lignite here, however, is below water level, except at extreme low stages. It has been dug in small quantities and used locally. It is evidently the same as the seam noted in the Grand Ecore bluff, but is of a decidedly better qualit5^ remaining in large cuboidal masses or chunks after having been exposed to the air for months. Cedar bluff is particularly rich in Indian relics. A walk of a few mimutes over any plowed field is sufficient for the collection of hands full of fragments of pottery. About a mile to the south of the bluff on the St. Maurice road a Lower Claiborne prairie is struck, which shows the character- istic marine molluscan species and fragments of light yellowish limestone. Marthaville . — A cut on the railroad at this place shows very large, hard, light yellowish calcareous boulders. They are char- 72 Geological Survey of Louisiana [Sect. acterizedby a Lower Lignitic fauna including Osirea thirscc var., Levi/usus iyidentiis, and other species characteristic of this horizon. Specimens from Sodus, from concretions presumably of the same horizon were scarcely identifiable. One the north-east one-fourth of Section 2, 9 N., 12 W. Sabine parish, mineral water is obtained from Ferrell's well. Dr. J. H. Mumford collected several ferruginous, clay concre- tions near this well that show an interesting, though poorly preserved marine fauna. \'enericardia planicosta, Yoldia kindlei, Vohdilithes pctrosus, Calyptraphorus , Levifusics Plenrotonia silicata, and other Pieurotonice , seemingly of a lowest Lignitic or Midway aspect. Mansfield. — This region was first described geologically bj' Hilgard in 1869 and much more fully by the same author in 1873. He called particular attention to the limestone, concre- tionary layers so often seen in this portion of the State, and con- cluded from the fact that they contain fossil leaves that they were of fresh water origin. This seemed such a departure from the ordinary run of lignitic Tertiary beds that he gave a new name to the group of sands and clays containing these con- cretions, calling them the Mansfield group. (See further under Historic review.) The nature of the material that underlies the soils in this gen- eral region is well shown by the following section made from an outcrop in the gorge just west of the town. 5. Soil and red sand 5 ft. 4. Sand with iron streaks 10 ft. 3. Sand with a few light bluish clay streaks 5 ft. 2. Very light, or yellowish calcareous concretions 2 ft. I. Sandy, laminated, sands, with iron streaks above ; light sands, medially ; bluish laminated clays below 30 ft. As might be anticipated by the character of the rocks exposed in this section, the hill land about Mansfield is decidedly sandy. But there are broad bottom lands adjacent to stream courses, of a more clayey and loamy character, and very productive. To the southwest and west, calcareous black land prairies are reported. At Logansport on the Sabine extensive deposits of lignite are II] General Geology : Lower Claiborne Eocene 73 described. Hilgard has noted similar beds in the Dolet hill. In fact, outcrops of this substance are of frequent occurrence in this part of the State, and we are prepared to reaffirm Hilgard' s statement ' ' that lignitic strata crop out on both sides of the dividing ridge from Pleasant hill to Mansfield, towards Shreve- port. Various estimates are given as to the thickness and character of these lignite beds. The whole subject must be taken up systematically and monographed in some future annual report. Grand Ca7ie. — Going north from Mansfield, numerous arena- ceous deposits are seen along the roadside, some showing flow and plunge structure. Post-oak fiats with mounds are here extensive. Red iron-stone concretions are here and there abun- dant. Yellowish concretionary limestone was noticed often near Grand Cane. Stonewall. — Calcareous limestone boulders and lignite are noticed about Stonewall. The soil and topographic features are similar to those around Mansfield and Shreveport. Shrevepori. — (See special report on this area included in this report.) lyOWER Claiborne Stage Preliminary Remarks The beds that belong to this stage have been referred by the earlier writers on Louisiana geology to the ' ' Vicksburg, " " Jack- son," " Mansfield," groups or stages, as it is stated in our His- torical review (see Hilgard and Hopkins, Reconnaissance Period). After a better understanding of the inter-relationship of the Eocene deposits east of the Mississippi was worked out, chiefly in Alabama by Smith and Aldrich, references were made to the " Claiborne " of Louisiana.* To Hon. T. H. Aldrich of Birmingham, Alabama, science is mainly indebted for the recognition of this stage in Louisiana. It was he to whom many of the fossils collected by Johnson in 1885 were submitted. With his aid, Johnson was able to state in his report on the * Mineral Resources of the United States, 1883, p. 554. 74 Geological Survey of Louisiana [Sect. iron ore of L,ouisiana and Texas, that it is the lower portion of the Claiborne group of strata that occurs in Louisiana and Texas. He properly refers a portion at least of the St. Maurice bluff to this horizon. Also the bluff at Natchitoches, and many local- ities in Bienville, Claiborne, Webster, and Bossier parishes were properly arranged under this stage. It has remained for this survey to rectify the work of former reconnaissances west of Red river. Areal Distribution The map. — All along the northern tier of counties, from the Dorchite to the Onachita there may be uplifts of beds belonging to the Lignitic stage, for molluscan remains are generally want- ing in these parts. The general trend of the various geological stages of this part of the State would indicate that all this terri- tory is Lower Claiborne as mapped. The doubtful area about Shreveport has been elsewhere dis- cussed. (See Shreveport area.) Otherwise the mapping of the Lower Claiborne may be regarded as approximately correct. Localities (Sabine parish) Low' s creek belozv Sabinetown, Tex. — This locality has already been referred to in connection with the Lignitic stage. At the ford perhaps one-fourth mile below the water mill on this creek, ledges of Lower Claiborne calcareous rock occur, char- acterized, among other fossils b}' Ostrea falciformis. Lower Negreet. — Near the mouth of this bayou there is a cross bedded conglomerate, very ferruginous and rough in appearance with quartz pebbles and clayey and glauconitic nodules, contain- ing fossils of this stage. A bed of white quartz sand 8 ft. thick lies above this conglomerate. Almost nothing of the salt-works that once were in operation a mile or so farther up stream could be found. It appears that some of the wells were in the bed of the bayou. One old shaft was seen on the left bank. According to Mr. Dan'l Vandegaer the process of obtaining salt here was usually as follows : Hollow cypress logs were sunk II] General Geology: Lower Claiborne Eocene 75 vertically in the bayou over the places where the saline water seemed to rise ; these were cut off at such a length as to be always above the surface of the water. The contents of the logs was pumped out and run off in kettles and evaporated to salt. The light blue clayc}^ beds around the shaft just mentioned and in a little rivulet close by, contained some very imperfectly preserved marine shells. Nothing was found to lead us to sup- pose that the deposits hereabouts were other than Lower Clai- borne where the general stratigraphy of this region would place them. Quite a large tract, several acres, was noticed not far from the north bank of the bayou nearly devoid of vegetation. Simpkhi' s place . — Mention has already been made of Lignitic strata occurring along streams to the southeast of Negreet P. O. The hill or ridges are often strewn with ferruginous sandstone chunk showing within limonite nodules. Near the northern border of the Simpkins' place a tj-pical " black-land " soil is found, ver}' calcareous, showing boulders of light A-ellow lime- stone and many marine fossils. Some collected are : Osb'ea falciformis, O. Johnsoni, an Orbitolite, Peden, Cypr^za, and Tjir- ritellacarinata. Near Mr. Simpkins' house the fields are some- times almost covered with red ferruginous chunks. Yet these fields are said to bear fine crops. The reason is very evident. These ferruginous rock fragments are before exposure, as when first obtained in digging a well, of a grayish greenish or bluish hue and are replete with marine organic remains. It is the leaching of this material, calcareous and glauconitic, that supplies the soil with the elements that it needs in plant production. The red color is simply due to oxidation of the iron already in this material though in a different chemical combination and of a different color. From the general lay of the land we assume that these exces- sively ferruginous layers are higher stratigraphically than the "black lands" with their limestone boulders mentioned above. Certain it is that above these ferruginous layers, come sandy beds some 30 feet or more in thickness, capped with large rough and micaceous sandstone chunks. The latter seem to be desti- tute of organic remains. This particular calcareous and red land belt extends, with 76 Geological Survey of Louisiana [Sect. some few interruptions, from near the mouth of the Negreet to Natchitoches. Leech neighborhood. — Going towards Many from Simpkins' place, one follows nearly the trend of the red lands. But they are often obscured by the overlj'ing sandstone deposits men- tioned above. Near the Church and again in the Leech community some of the fields are of an astonishingly red color, and the red rock frag- ments seem to cover the fields. Likewise on toward the east, by Jas. Leech's, the red beds are very strongly developed. Perhaps one-fourth mile east of the last mentioned place fragments of slightly yellowish white limestone occur in a little depression that crosses the Many road. This is associated with a few feet of whitish marl, as at Natchitoches. About 7 miles from Many, or 2 miles N. E. of Jas. Leech's, the red lands cease abrupth' on the Many road, and the Lignitic sands, with slight but constant slope to the south, furnish broad expanses on which flourishes the long-leaf pine. About the sole associate of the latter seems to be the hardy ill-formed black-jack oak. There are occasional abrupt descents to the north where the edges of the southward dipping strata come near the surface. Some of these beds are clayey, wet and cold. They are charac- terized by the usual varieties of oak and short-leaved pine. Then another sand-covered gentle slope to the south occurs whereon luxuriates the long-peaf pine. South of Many. — The railroad cuts south of Many are referred to in several places in this report. For some distance they show nothing but sands and clays of the Lignitic period. But, perhaps 4 miles south of the station, the Lower Clairborne beds come in showing a marked uncon- formity with the Lignitic strata below. Fossiliferous red lands were seen by Veatch two miles still farther south on the same railroad. (Natchitoches Parish) Victoria Mills. — Indurated calcareous beds crop out in the log tram-way back of these mills. From a soft layer below these II] General Geology : Lower Claiboene Eocene 77 beds a sack of marl was obtained for analysis, but has not 5'et been reported upon. The hill back of the mills contains several ledges of Ostrea falciformis in impure limestone. Provencal. — A very typical lyower Claiborne exposure occurs on the north side of the R. R. track about one-half mile west of Provencal. Ostrea falciformis is in great abundance associated with a small Orbitolite, and imbedded in a light yellow clay marl. The region has the usual calcareous-land flora. Other local beds of ' ' red land " or " black land ' ' were seen or heard of about Provencal. Railroad cuts were examined as far castas Robertsville, where an interesting and fossiliferous out- crop occurs. Ferruginous nodules about one-half to one inch in diameter contain Lucincc and large numbers of Aira rhomboi- dalis. The light gra}' clays have scarlet red blotches as at several other places. The residual soil is of a light gray, and a slightly reddish hue. Two miles south of Provencal, on the Leesville road, the same phase of the Lower Claiborne is met as seen on the R. R. west of Provencal or at Natchitoches. Another interesting locality, where marl and shells have been reported, is at a Mr. Stephen's house, half waj- between Robe- line and Natchitoches. The localit3-was not visited b}^ us, hence we are unable to say whether it belongs to the Lignitic or Lower Claiborne stage. Natchitoches. — (See special report on this area.) Black lake. — Small black land prairies covered with an abun- dance of 03'ster shells are very common in Natchitoches parish north of Black lake. Section 4, 11 N., 16 W. — Near James Thompson's house, two and one-half miles north of Black lake, i mile west of Remj^ creek and south of the Saline-Weaver's ferry road is a small prairie covered with Ostrea falciforynis, and O. johnsoyii. It is on the ver}^ crest of the hill, 70 feet above the surrounding hollows and 90-120 feet above Black lake. Just south of the prairie and 6 feet below it is a bed of quartz and chert gravel. The creek west of the knoll shows the following sections : 78 Geological Survey of Louisiana [Sect. 1. Ostrea bed — top of hill 3 ft. 2. Greenish gray to slate colored clayey marl, joining black soil. A few, poorly preserved shells occur in this layer. The best preserved was a strongly ribbed Corhila 50 ft. 3. Dark brown sand with plates of iron 8 ft. In the creek east, layer 3 was not seen. In the creek bed are numerous very long limestone concretions. The sides of the hill are covered with gravel and furruginous pebble conglomerate and sandstone, but in no place did the gravel unquestionably pass under the marl. Similar small prairies with the characteristic oysters, Ostrea falciformis, and O. Johnsoni var., occur north of the locality at the following places : Sec. 5-8, Sec 21-28, 12 N., 6 W. and at Black prairie hill N. E- ^4 Sec. 23, 13 N., 7 W. (Winn Parish) SI. Maurice. — Here the Lower Claiborne beds are well exposed on the left bank of Saline bayou near its mouth. Plate 5 herewith given shows well the most important features of the bluflf. The view is taken looking down-stream. The ledge in the baj'ou, showing a steep southerly local dip is composed of reddish cla}' ironstone. Then succeed 5 feet of bluish, blackish, or brownish barren clays. Above are blue clays, 5 feet with arenaceous ferruginous concretions. Shells are abundant in this layer. Still higher are 10 ft., of brown, brittle clays with yellow flakes. Finally, the upper 25 feet of the bluff are composed of brownish laminated sandy clays, becoming lighter in color and more sandy towards the top of the bluff. The character of these underlying beds has less influence over the character of the soils in this region than might at first be supposed, for they are often concealed by Lafayette sands and gravels. Concerning the paleontology of this locality see historical part of this report, p. 34 and especially next year's report. Between this locality and Wheeling the country is somewhat hilly at first near the Red river, but becomes more rolling or level to the east. II] General Geology : Lower Claiborne Eocene 79 Rather abrupt ascents and descents are frequently met with between St. Maurice and Congo P. O. In these regions the soil is sandy on the hills but more clayey in the bottoms. A mile or so north of Congo, Lower Claiborne beds are met with, characterized by white limy concretionary lumps, a light 5'ellowish soil, very teuaceous when wet, boulders of light yel- lowish limestone, with fossils, and the usual scrubby growth of trees. Some beds have already been noted on p. 71 south of Mr. Kieffer's. Couley. — The more ferruginous layers of the Lower Claiborne are well exposed on the hills near Couley, S. 10, 10 N. 5 W. In the stream beds, mau}^ exposures of bluish claye)' marl were noticed and samples were collected for analysis. Coochie brake. — East of Coochie brake the summits of the hills are in the neighborhood of 60-90 feet above the brake and show now and then great masses of red sandy iron ore concre- tions, or chunks ; but no fos.sils were observed in them. The region is generally sandy, and long-leaf pine is abundant. Winyifield. — On approaching Winnfield from the Brake, after passing over long stretch of fairly level country, broken now and then in the vicinity of streams, a somewhat varied region is reached about 8 miles from Winnfield. It is not, however, until the 5 mile-board is nearly reached that the calcareous red beds crop out along the road. There are here veritable red lands, but of what extent it is not possible at present to state. Similar, though far less fossiliferous layers are found within four miles of Winnfield in the road, but the most abundantly fossiliferous layers are found to the northward towards the " Marble " quarry (see Fig. 3, p. 57). About Winnfield no traces of red land were seen. Good brick clay, however, abounds, and the Court house stands as a witness of the good quality of the clay. Lerch, notes the occurrence, of marl and " rotten shells " in the material thrown out in digging wells in this vicinity . New Hope church. — About one-half mile northwest of this church (11 N., 4 W., near the house of John Neil), numer- ous ferruginous concretions are to be seen. They are replete with casts and impressions of a small gastropod {Turritelld) . 8o Geological Survey of Louisiana [Sect. Sparta- Moyitgomery road, 24th mile-board. — On the vSparta- Montgomery road, about one-half mile south of 24th mile board ferruginous concretions are quite abundant at the road side. About a fourth of a mile north of this and at a slightly lower level there is a strip of black land exposing large yellow limestone boulders, in every way similar to limestone boulders which are so common on the little prairie spots in northern Natchitoches. Both the ferruginous and limestone concretions contain many casts of marine shells. This locality is just south of the house of Mr. James Jackson, about Sec. 12, 11 N., 5 W. Twin prairie is a little patch of black land of about 60 acres situated one-half mile southeast of Saunder's church (about Sec. 12, 11 N., 5 W.). The ground is covered with very small limestone concretions and in some of the gulleys Lower Claiborne fossils are exposed : Anoniia, Plicatiita Jilauientosa, Pseudolivc vetiista, 2ir\d Ostreafalci- formis were among the specimens collected. Vasherie branch. — On this branch of White Oak Creek, about 10 miles northwest of Winnfield, Lerch and Vaughan record a Lower Claiborne exposure with a stratum of calcareous marl 20 feet thick.* (Grant Parish) Georgetoivn. — We were not able to find any traces of Tertiary deposits in the vicinity of this place. The mill, store, and sta- tion are surrounded on all sides by level alluvial lands. Vaughan cites Lower Claiborne fossils from this place. f (Caldwell Parish) Columbia. — The Lignitic sands and clays, belonging perhaps to the Lower Claiborne stage are exposed very advantageously for study around the station and for some distance to the south along the railway track. Nowhere in this part of the State are there better outcrops. *See Lerch's 2d Report, etc., p. 89 ; and Vaughan, U. S. GeoLSur., Bull. 142, p. 31. fU. vS. Geol. .Sur. Bull. No. 142, p. 17. Geological Survey of Louisiana, Report, i? Plate 6 t r^ ^> ft f:*^^ .^ V ^^ "SW CUT SOUTH OF STATION, COLUMBIA, LA. II] General Geology: Lower Claiborne Eocene 8i Hopkins * and Lerch t have already given sections of several of these exposures. Hopkins most important section was taken " one mile back of Columbia " in the hills. It shows sands and clays of various colors and thin seams of " iron rock." He noticed the abundance in certain layers of fossil leaves, and mentions a lignitized log "showing structure very prettily.'' Lerch's best section was taken at the first important outcrop on the west side of the railroad going south from the station. We have several photographs of this interesting place, showing a non-conformity of the layers to the right and near the track with those to the left and above to the top of the bluff. One of these views is herewith reproduced. (Plate 6.) Great trouble is experienced by the railroad officials in keep- ing the track from moving laterally or sinking in the mud in these deep cuts. This is due somewhat to the fact that layers of sand, approaching "quicksand" alternate with impervious clay layers. The water is held by the clay layers and this tends to make the sand very movable. The diflficulty in this region, however, is not serious ; it can be obviated very generally by widening the cut a few feet, and securing proper drainage for the track. Lerch mentions a fine bed of lignite on Coal creek near this town. We did not visit the outcrop. Dicotyledinous leaves, however, are to be found in great abundance in the clayey layers of these various sections. Here, then, will be an excellent opportunity of determining the practical value of fossil leaves in determining the age, or horizon of the formations of this region. An endeavor will early be made to secure large quantities of these fossils. Below the station on the hill slope towards the town, a layer of calcareous, light-colored sandstone is found, which has been quarried to a slight extent. It is but a thin stratum and can never be of any considerable economic importance. On the west of the Ouachita the land is very hilly and broken, and most beautiful views are to be had from these high hills for *i'st Report, 1869, pp. 83-84. f Lerch's 2d Report, p. 83. 82 Geological Survey of Louisiana [Sect. miles up and down the river. To the east of the Ouachita stretch wide alluvial plains. In general there would seem to be very little calcareous matter in the substrata of this region. Towards 011a, however, white calcareous concretions are found in wells. Lone Grave bluff. — Hopkins gives a section at this locality. From the character of the various strata named (white sand, laminated lignitic clay et al.), it is evident the same condition of deposition obtained here as at Columbia, and the beds are doubt- less of the same age. (Ouachita Parish.) Monroe. — This is a region very difficult to study geologically •on account of the lack of good sections. Lerch reports Clai- borne fossils, from the artesian well bored at this place under the supervision of W. A. Strong. Specimens supposed to be these have been sent us from Baton Rouge but they are almost cer- tainly from Smithville, Tex., as determined by the character of the fauna and the very color of the embedding material. (See Lerch's ist Report, p. 21.) They were from a depth of 185 feet, in a black clay stratum. Calhoun. — The red sands and gray clays along the railroad from Monroe to Calhoun have already been described b}^ Lerch in his first report pp. 21-22, 25. (Jackson Parish.) Our information regarding the geolog}' of this parish is very meagre. Johnson * has mentioned a few iron ore deposits of apparently limited extents, and Vaughanf has given two locali- ties of Lower Claiborne Eocene fossils on the Liberty hill, Vernon road. One 10 miles east of Liberty hill, the other 15 miles east of the same place. (Lincoln Parish.) Vinhig mills. — This parish has, as yet, received but little attention. Johnson mentions high hills capped with ferruginous *Iron Ores of La. and Tex., p. 47. -fU. S. Geol. Sur. Bull. 142, p. 32. n] General Geology : Lower Claiborne Eocene 83 sandstone in the vicinity of the Vining mills. Fossils were obtained from a greensand reached in a well sunk by Mr. Hud- speth in the bottom near this place.* Vienyia. — " In the vicinity of Vienna good limonite is abun- dant on the surface and it occurs widely scattered over the red lands which extend from Vienna to Mr. A. G. Reed's, Sec. 9, 19 N., 4 W., a distance of eight miles." — Johnson. Redwiyie' s spring. — Johnson gives a section at this place, and states that the greensand is 12 feet thick. In a foot-note he states that ' ' tests of this greensand show it to contain potash and also to be highly phosphatic." Lerch mentions the occurrence near here on Judge Graham's plantation of fossil casts in clay ironstone concretions. Vienna seems according to him, to be the center of a red-land area.f The fine sections exposed along the V. S. and P. R. R., are illustrated by Lerch on a folding sheet placed opposite p. 26, of his first report. Attention is called to the disturbances of these strata. Nine miles west of Ruston. — Nine miles west of Rustonon the Arcadia-Ruston road a coarse iron sandstone containing many fossils crop out in the road-side. Hardly enough material was collected at this locality to render its identification beyond question, as the locality shows a tendency to combine Lower Claiborne and Lignitic forms. More material will probably prove it to be Lower Claiborne. (Bienville Parish.) Sec. 31, 14 N., 7 W. — About 200 yards east of the Campti Sparta road on the Lake village and Venon road is a typical Ostrea-stxe^n prairie. Above the Osirea layer are numerous concretions, containing very indistinct casts. The common Osirea falciformis and O. johnsoni were seen here. This is the locality which Lerch refers to in his first report as Cretaceous. \ * Iron Ores of La. and Tex., p. 45. f 1st Report, p. 26. X Bull. La. Expt. Station, part i, 1892, p. 14. 84 Geological Survey of Louisiana [Sect. Sparta. — North of King's salt works on the Coushatta-Sparta road the hills rise very abruptly 120 feet. The material seems to be almost entirely a light colored, rather fine sand. Rapid erosion gives rise to some very interesting topographic forms ; great, perfectly shaped ampitheaters are common near the heads of the valleys. On the whole it is a topography without sharp angles. In places natural land-locked ponds were seen, looking like great sink-holes. About six miles from Sparta long-leaf pine takes the place of the short-leaf and continues to within a mile of the old town. At Sparta nothing is to be seen but fine, light-colored sand with coarse iron sandstone boulders. There seems to be no good reason for separating this sand from the adjacent Claiborne beds. Liberty Hill. — Nearly all the hills in the vicinity of Liberty hill are covered with ferruginous concretions filled with casts of Lower Claiborne fossils. The best locality seen was above, i ^ miles northeast of the village on the Ruston road. Near a graveyard, north of the stores, fossiliferous iron concretions were seen capping the hill. They were here underlaid by beds of coarse iron sandstone and by the gray Arcadia clays of Lerch. This would seem to show that the Arcadia clays are merely a subordinate bed of the Lower Claiborne.* The fossiliferous Lower Claiborne material continues for about 10 miles north of Liberty hill on the Arcadia road. Arcadia. — Dr. Givins, at Arcadia, has kindly furnished the following section of the well on his place : 1. Surface Soil — red and white sandy loam 3 ft. 2. Mottled red and white clay 7-8 ft. 3. White clay with some red 5 ft. 4. Dark brown or bluish black tenaceous clay, mottled with white and red, containing some sand and selenite crystals, shows traces of fossils and leaves. 10 ft. 5. Hard red iron concretions, containing fossils and some phosphate of iron i >^ ft. 6. Pure white sand 2 ft. 7. Green sand with fossils 10 ft. 8. Hard rock not passed through. *Also referred to by Vaughan, Bull., U. S. Geol. Surv., 1896, p. 21. iij General Geology : Lower Claiborne Eocene 85 Water from above layer. • " 5 " is reported to be slightly sulphurous. Water for " 7 " is strongly impregnated with lime. In the base of the first cut west of Arcadia are about 3 feet of dark sandy clay with thin clay partings, and patches of greensand. Several shark's teeth and specimen of Byssoarca,Cardium and Deyitalium were found here. About three miles west of Arcadia is the ' ' hog back " railroad cut. A rather soft layer, bearing greensand is here overlaid by harder clayey material. The cut was originally made through the upper clay, and a little way into the greensand. The weight of the top material squeezed the greensand up into the cut. The local section boss states that the railroad company has had to lower the track three times, each time about three feet. It is this sort of action that Hilgard regards as having formed the mud-lumps of the passes of the Mississippi. A few casts were found in the lower part of the greensand. Gibbsland. — About two and one-half miles east of Gibbsland a light chocolate colored clay, about 8 feet up in the cut contains many casts oi Leda, Venericardia, Denialiiim and a small Echino- derm. At the base of Mt. Ivcbanon are easily identified Lower Claiborne fossils. HammetV s branch. — This may be regarded as once of the classic Lower Claiborne localities of the State. It is situated in the S. W. one-fourth Sec. 30, 18 N., 6 W., about 2 miles northeast of Mt. Lebanon. The main exposure is in a little gully about a quarter of a mile from the road. As this section has been published by Johnson,* Lerchf and Vaughan,| it is hardly necessary to republish it here. (Bossier Parish.) Coushatta bluff. — This and a few other bluffs on Red river were examined by Hopkins and Johnson, and later by Veatch of this Survey. (See special report on Shreveport area.) Johnson points out how that from here southeasterly to Rocky mount *5oth Cong., 1st Sess., Hou. Ex. Doc, vol. 26, No, 195, 1888, p. 20. tBull. for Expt. Station : Geol. and Agr., part i, 1892, p. 20. JBull. U. S. Geol. Surv., No. 142, 1896, pi. i, fig. 2. 86 Geological Survey of Louisiana [Sect. and easterly to Red land there is an elevated expanse of ferru- ginous " red-lands." Three miles east of these bluffs he records the occurrence of marine shells in shallow wells. Red land area. — He reports iron ore in the N.W. %, S. E. %, S. 28, 22 N., 12 W. Again in N.W. ]i, S.W. i^, Sec. 20, 23 N., 12 W., where casts of fossils occur. Sections 18, and 26, 22 N., 12 W., contain ores and fossils. The Red land region was visited and reported upon by Har- ris* in the Arkansas Survey Report for 1892. The Pope Joy cut and that at Roberta, on the St. L. S. W. R. R, are described in a detailed manner. Fossils from the red land area are named. Bellevue. — East of Lake Bodcaw other red lands appear. They are described by Johnson and Veatch. The former says : In southern Bossier is an island-like mass of hilly older Tertiary material entirely surrounded by comparatively level upland flats of probable Port Hudson age. Bellevue, Fillmore and Haugh- ton are situated two miles from Bellevue ; iron sandstone and iron concretions abound along the roads. A few poor fossils were collected here but hardly enough to prove the age of the bed. About Fillmore there are a few poor fossils in iron concretions. Johnson's section, from a deep wash below the jail at Bellevue shows well the character of this region. It is as follows : 1 . Reddish surface clay and sand with some fragments of geodes 30 ft. 2. White clay and sand 20 ft." 3. Stratum of sand i ft. 4. Dark lignitic sand 15 ft- 5. Blue greensand 2 ft. 6. "Soapstone," i. e., laminated smooth brown claj', of which there can be seen to main stream of branch, where there is an alluvial bed one mile from Lake Bodcaw, only 6 ft. *Ann'l Report, Geol. Surv., Ark., 1892, vol. 2, pp. 179-1S0, Pub. 1894. II] General Geology : Lower Claiborne Eocene 87 (Webster Parish.) Minden. — On the west side of Crow creek in the Homer-Min- den road, gravel appears on hillsides. The soil is generally a shade lighter and more yellow than on the red lands. From eight miles northeast of Minden the gravel is quite com- mon. The soil is red or yellowish-red and rather sand)'. The relief is very small and the bottoms quite wide, in marked con- trast to the red land topography about Homer. Exposures of gray claj' are common about Minden. Going north from Minden on the Minden-Sykes ferry road the most noticeable thing is the great abundance of gravel. The soil is a fine gra}' sand and occasionally graj^ loam. Red sandy soil is comparatively rare. Northern part of parish. — One mile north of Mr. Sam. Mem's house (S. W. %, N. E. ^, Sec. 19, 20N., 8 W.) the road passes into what appears to be the bottom, but which turns out to be the second bottom. The bottom of Flat Lick creek is nearly, if not, a mile wide. On the Lewisville-Minden road at the 13 mile- board a very red sand)- soil sets in. This red sand)' soil continues to the red-land hills, of which it forms an outlier. The red hills rise very abruptly above the sur- rounding country. They are covered with ferruginous concre- tions and sandstone. The summits of the hills are 210 feet above Black creek. North of the red hills, which are from a mile to two miles across, the land is reddish yellow sand or sandy clay with occasional patches of gray "dirt" land. In a little branch one-half a mile northeast of Leton (Leton is a new post-ofSce in the N.W. ^, Sec. 36, 22 N., 9W.) in a small branch the following section is exposed : 1. Gray " dirt land," a sandy loam 2 ft. 2. Gravel and reddish rock i ft. 3. Irop sandstone i ft. 4. Green sand with little white spots of lime, no shells . . . i ft. 5. Slate-colored clay to water level i ft. A mottled gray and red clay, representing the Arcadia clays, is seen in nearly all the road gullies, about half-way up the sides of the hills. Gravel is seen here and there, and is quite common near Shongaloo. 88 Geological Survey of Louisiana [Sect. About half a mile from Syke's ferry the road enters the level second bottom. Natural mounds are quite numerous. The soil varies from a gray clay to a pure gray sand. The present bottom of Bayou Dauchite is about half a mile wide and at Syke's Ferry is on the west side of the Bayou. From Serepta to Cotton valley the relief is very small indeed. The prevailing soil is a pure gray sand. Johnson describes briefly the iron ores of this parish, and determines their age as follows : From fossils collected in N. E. % Sec. i6, 20 N., 9 W., and in S. 2, same township and range, and in S. 25, 21 N., 9 W., it appears that these red lands are the outcropping of Claiborne marls, rich in greensand, which were traced northward from Minden. (Claiborne Parish) Lisbon. — Around Lisbon is a red sandy clay soil, apparently of considerable agricultural value, for the country looks like a very thrifty prosperous strip of land. The larger creeks have great flat bottoms. Middle Fork bottom is in this region about a mile and a half wide. It is partly in cultivation. The hills on the southern portion of the bottoms have a height of about 100 feet. Some of the ironstone concretions which occur in this region, when broken open, contain a nucleus of gray phosphate of lime. Several of these concretions were picked up on the hills on the south side of Middle Fork bottoms and on McGar- land's creek ; and, Mr. Maurice Bird of the North Louisiana Experiment Station has shown that the concretions contain from 15 to 20 per cent of phosphoric acid. It is hoped that larger deposits of these may be found. Haynesville. — Around Haynesville the topographic relief is not so great as farther east. Gray sands and clays occur in the road cuts, and gravel crops out on the hillsides. Homer. — Six miles northwest of Homer on the Homer- Haynesville road the light gray sands of the Gordon region are replaced by red lands. These red lands occur with scarcely an interruption to Homer. At Homer the railroad cut shows 18 feet of light yellow to white strongly cross-bedded sands with t -s 11] General Geology : Jackson Eocene 89 horizontal layers of white claj- pebbles, and near the top, some iron concretions. The red lands with very marked topographic relief continue for about 6 miles from Homer, on the Homer-Minden road. The iron concretions then commence to be conglomeritic, and about 8 miles from Homer large quartz pudding-stones are quite numerous. The first really noticeable alluvial valley is that of Crow creek which is about half a mile wide. Judging from the fields seen here it seems capable of producing good oats. (Union Parish) The northern part of Union parish is very heavily covered with sands in part beronging to the underlying Eocene strata and in part to the Lafayette gravels which are found over many of the hillsides. Very fine exposures of red and white sands are to be seen in the deep gullies around Walnut home and Wal- lace's store. On the eastern side of the parish is a low strip of pine flats, presumably belonging to the Port Hudson period. These are well developed on the Ouachita city — Farmersville road from 3 to 8 miles west of Ouachita city and on the Alabama-Marion road to within 5^ miles from Marion. D'Arbonne. — Along the D'Arbonne and its branches the country is very broken, a relief of about 150 being quite com- mon. Mosley's bluff is an abruptly sloping hill 80 feet high. The soil is composed of sand with some iron sandstone. Near the top are layers of red sands separated by occasional thin lay- ers of clay. Wherever the clay layers occur they give rise to a spring horizon. Around Farmersville high sandy hills covered with ferruginous sandstone and gravel, lie about in the northwest- ern part of the parish. Toward Junction city the relief is much less marked. The land is rather low and the soil a pure grained, silty sand. Jackson Stage Distribution The map. — The general distribution of this terrane is shown on the accompanying geological map of the State. It is based 90 Geological Survey of Louisiana [Sect.. wholly on the character of the fossil remains found at various localities throughout the entire extent of the belt. Our historic review shows how erroneously various deposits from Red river to the Sabine have been referred to the "Vicksburg," "Mansfield" and other horizons quite without regard to any study of the fossil remains they so well display. We have as yet found no trace of Vicksburg deposits west of Red river. Localities Bayou Toro. — On the east bank of Bayou Toro in the S. E. one-fourth of the N. W. one-fourth of Sec. 6, 3 N., 11 W., Vernon parish, is a small bluff about 20 feet high containing many Jackson fossils. The shells scattered through the clays are very much decayed and quite diflScult to obtain. Scattered through the clay are large dark-colored limestone concretions. They are particularly abundant in the little stream which enters Toro just south of the bluff. It was from these limestone bowl- ders that most of the fossils were collected. Outcrops of typical Grand Gulf sandstone were seen in the hillside about 50 feet above this locality. Hilgard in 1 869* described a seam of shell limestone with "Vicks- burg" fossils at the base of the Grand Gulf rocks on Bayou Toro. The location of this bed, corresponds very closely with the bed from which we collected fossils. Rattan P. O. — The bed of Bluff branch on the place of Mr. J. L. Peace, near Rattan P. O. (N. W. one-fourth Sec. 8, 4 N., II W.) shows an outcrop about 8 feet high composed of a fine yellow sand containing many small shells. Several larger shells were obtained from a well sunk at Mr. Peace's house. These fossils indicate that the beds belong to the Jackson stage. Material which is very strikingly similar to that just mentioned occurs on the Leesville-Provencal road between Middle and Sta Barba creeks about 10 miles south of Provencal. This is very nearly in line with the Jackson outcrops. *Am. Journ. Sci., 2d voL 48, p. 339. II] General Geology : Jackson Eocene 91 Montgomery. — This is already a classic locality in Louisiana geology. (See under Historic Review.) The accompanying illustration shows well the general appearance of the most important outcrop in this region. The following beds are exposed : • 8. Orange sands 5-50 ft. 7. The above grade downward into pebble beds 5 ft. 6. lyight sands 3 ft. 5. Sands, slightly lignitic 5 ft. 4. As 5, separated by clay layer 8 ft. 3 . Thin light sandy clay 2. Bluish marl, fossiliferous 5 ft. I. Lignitiferous clays 15 ft. Large collections were made at this locality and will be reported upon next year. Owing to a very heavy deposit of Lafayette material over these Jackson beds the influence of the latter upon the soils of the region is greatly diminished. Towards Wheeling, on the east side of Nantaches bayou, very extensive deposits of ferruginous sandstone and sands were observed. The hills are 50 to 150 feet in height above the Bayovi. The ravines, although numer- ous, seem to show no traces of fossil remains. The soil of the hills is excessively sandy. Gravel layers are numerous, occur- ring above the heavy sandstone ledges, and below the gray sands of the hills. Tancock' s prairie. — Just south of Ben creek or the northern edge of Tancock's prairie many specimens of Ostrea tris^onalis are scattered over the ground. The limestone concretions which accompany this outcrop contain in addition to other forms very large specimens of Haminea grandis. These with other speci- mens collected have proven the Jackson age of the locality. Hilgard refers this to the Vicksburg.* TiiHos. — This station is in a Jackson prairie. In light grayish sandy clay in the railroad cuts there are many calcareous concre- tions. In the bottom of some of the wash-outs by the side of the track a bluish clay appears. *Am. Jour. Sci., 2d series, vol. 47, 1869, p. 340; Supl. and Final Report of a Geol. Record of La., p. 33. 92 Geological vSurvey of Louisiana [Sect. A typical cut can be seen, along the track about one mile south of the station. Zeuglodon bones are fonnd here. A vertebra purchased of Mr. Porter shows an oyster grown upon it, proving that the Zeuglodo?i died and its flesh decayed before the oyster was attached. In an old field about three-quarters of a mile north of the sta- tion, along numerous little washes in the field, many well-pre- served fossils are obtained. Ligniferous clays appear in the branches to the north. A cut one mile north of the station shows southward dipping lignitic clays, superimposed by what seems to be Jackson marly clays. There seems to be a slight nonconformity between the two classes of deposits. Olla. — Going still farther northward from TuUos we saw no good exposures. Gray buckshot clays appear in shallow cuts. At Olla wells are said to penetrate marls with calcareous con- cretions. Lerch reports fossils from the region in Sec. 34, n N., 2 H.* Ouachita river. — The Jackson is exposed in numerous places along Ouachita river below Columbia. It was in this region that Judge Bry found in 1832 the bones of the Zeuglodon and the shells which caused Conrad to refer the region to the Eocene, f In 1 84 1 Conrad described a new species, Cardinm nicolletti, from this region. J Hopkins visited Grandview bluff in 1869 and found several bones of Zeuglodon there. The presence of the little Orbitoline forms, which are common in the Jackson of this State, led him to confuse some of the beds northeast of the bluff with the Vicksburg. In 1866 Aldrich described a new species of gastropod, Haminea grandis, from Bunker Hill bluff. The first fossiliferous outcrops we saw on Ouachita river below Columbus were at Gibson's landing. In the bluff at this place is a layer of fossiliferous sandy clay about eight feet thick, and about fifty above water level. In a small branch about a mile *Bull. La. Expt. Sta., part i, p. 92. fjoiir. PhiL Acad. Nat. Sci., voL 7, 1834, p. 120. JProc. PhiL Acad. Nat. Sci. for 1841, p. 33. II] General Geology : Vicksburg Oligocene 93 north of this landing Zeuglodon vertebrae were found together with many shells. Bunker Hill bluff exposes about eighty feet of bluish gray clay containing very large selenite crystals. Near the top is a layer of large Venericardia planicosta in reddish clay ; at a height of sixty feet numerous casts of Pinna are in a yellow limestone concretion. Some of these casts look very much like the teeth of some very large animal, and we are not surprised that Judge Bry mistook them for such.* The main fossiliferous stratum is at the very base of the bluff. Grandview bluff, a mile above Bunker hill, shows about the same section. At Danville lauding, about 100 yards below the Caldwell and Catahoule parish line (marked Enterprise on lyockett's map) is a bluff about forty feet high composed of bluish yellow marl, very fossiliferous. The fossils have a slightly different appearance from the Bunker hill shells but are still decidedly Jackson in character. Wyant's bluff, about four miles above Danville, is about twelve feet high and shows blue clay with a few impressions and occasional pockets of shells. They are the same as found at Danville. OLIGOCENE Vicksburg Distribution Rosefield. — The Vicksburg stage is only very slightly developed in Louisiana. It outcrops south of Rosefield and probably occurs along Bayou Funne Louis. West of the Little river it has not been seen. Lerch has described a section along Shell creek, three miles south of Rosefield in Sec. 35, 11 S., 4 E., and Vaughan lists Dentalium. mississippiense , Ostrea vicksburgensis, Peden potilsoni, Area mississippie7isis, Byssoarca lima^ Pedunculus ardahis, Cras- satella mississippiensis, Meretrix sobrina, Balanophyllia caidifera, and Orbitoides mantelli, from this locality. *Am. Phil. Soc, Trans., new series, vol. 4, pp. 400-401, 1832. 94 Geological Survey of Louisiana [vSect. Shells were collected at several places between this locality and the Ouachita, but the specimens and notes were left with a gentleman at Rosefield to be forwarded, and have not yet been received. On the Harrisonburg road near the branch to Danville about a mile and a half south of Rosefield, fossiliferous yellow limestone concretions outcrop in the road. They are seen again near Sone's store, a mile farther south. About three miles east of Sone's store fossils are common near the saw-mill. Near the center of Sec. 31, 11 N., there is a small prairie with shells. In bottoms below, beds of lignite, which have at different times attracted prospectors, are reported. Grand Gulf HiSTORlCAI. Origin of the term Grand Gulf. — This formation was first named by Wailes, then State geologist of Mississippi, from a typical exposure at Grand Gulf, Mississippi.* It was described at length by Hilgard in i860 in his report on the Geology and Agriculture of Mississippi.! The Pascagoula formation (^Miocene). — In 1890, Mr. I,. C. Johnson discovered near Vernal P. O., Miss., and at other local- ities on the Pascagoula river a series of marine beds in the upper part of Hilgard' s Grand Gulf. These marine beds he named the Pascagoula formation. From the fossils collected at this locality, Gnathodon johnsoyii, Mactra lateralis and a large oyster resembling O. titayi of the west coast, Dall;]; has concluded that the beds are equivalents of the Chesapeaks Miocene. || It seems very probably that this formation is represented in Louisiana, in the southern part of what is now called Grand Gulf territory, but, thus far, it has not been recognized. Study of the Louisiana beds of this period. — In 18 16, William Darby recognized the northern edge of what is now called the * Report on the Agr. and Geol. of Miss., 1854, pp. 216-217. t Pp. 147-154, i860. X Dall and Harris, Bull. U. vS. Geol. Surv., No. 84, 1892, p. 164. II Bull. Geol. Soc. Am. vol. 5, p. 157, 1894 ; i8th An. Rept. U. vS. Geol. Surv., 1896-1897, part II, p. 339. 11] General Geology : Grand Gulf Oligocene 95 Grand Gulf, traced it from Sicily Island to the falls at Alexandria and correlated it with the bluffs on the east side of the Missis- sippi " above Natchez. "* In 1869, Hilgard skirted the southern boundary of the formation, passed across the same in Calcasieu and Vernon parishes and examined the northern escarpment on Baj'ou Toro and between Little river and Harrisonburg. During 1869 and 70, Hopkins made sev^eral trips across the State seeing the Grand Gulf at several points. His descriptions of the Grand Gulf in Louisiana are the most complete that have yet been published. t Johnson X and Lerch || have both examined portions of the northern boundary between Lena and Harrisonburg. Features of the Formation Characteristics. — This formation, which unconformably over- lies the Vicksburg,§ consists in the northern part of its territory, of a series of light colored sandstones and claystones of white, gray, or yellowish gray tints. The sandstone is generally rather soft, never over 20 feet in thickness usually only three or four. Beds of loose sand are unusual. The sand grains are commonly quite sharp. The hardness of the sandstone in a given layer varies very greatly and makes quarrying in this rock a rather uncertain business. Beds of sand will pass in a few feet horizontally into hard sandstones. The accompanying plate shows an exposure of Grand Gulf in a cut on the Texas and Pacific railroad, about three miles west of Lena. The lower sandstone bed in this exposure is rather uniform. The upper irregular one shows on a small scale the nodular masses in which the sandstone occurs. In some cases the amount of silicious cement is so great that the rock resembles a quartzite. Such is the typical Grand Gulf * A Geog. Des. of the State of Louisiana by William Darby, 1816, pp. 45- 46. t ist An. Repl. Geol. Surv. La., 1S70, pp. 98-102 ; 2d An. Kept. GeoL Surv. La., 187 1, pp. 18-26. X 50th Cong, ist Sess., House Ex. Doc, voL 26, No. 195, pp. 13-14, 1888. 11 BulL La. Expt. Stations ; GeoL and Agr., part II, 1893, pp. 93-98. § Hilgard.— The Later Tertiary of the Gulf of Mexico, Am. Jour. Sci., vol. 22, 1881, pp. 58-65. 96 Geological Survey ok Loulsiana [Sect. sandstone as exposed at Grand Gulf Mississippi. Hilgard gives the following description of it: "The typical Grand Gulf sandstone consists of grains of pellucid quartz, constituting a rather coarse sand, imbeded in an opaque, white, enamel-like mass of silex, which forms quite half the bulk of the rock." In the southern part of the territory occupied by this formation (possibly, in the part belonging to the Pascagoula formation) sandy clays and pure highly tenaceous massive clays of a gray, grayish-white, blue or green color are the rule. The color in the blue and green clays is often very intense, though on the surface they often appear yellow from oxidation. In some cases black lignitic clays are found in this deposit. Some of the beds are very calcareous and produce small black land prairies. In the northern part of the formation there are occasional beds of very fine white clay, locally called "chalk." The sandstones have resisted erosion much better than the underlying Jackson and Vicksburg beds. This has given raise to a somewhat level Jackson plain bordered on the south by a high, rugged line of hills. This very abrupt northern declivity is in sharp contrast to the gradual southern slope which carries the formation down to the level of the southern prairies. Distribution. — Large outcrops of Grand Gulf sandstone are to be seen at Harrisonburg and Sicily island. On the divide between the Ouachita and Little river the Grand Gulf extends well to the north, reaching a point near Rosefield. Along the edge of the formation "chalk" or fine white clay has been reported in a number of places. From Rosefield, according to Hopkins, the northern line of the Grand Gulf follows the Bayou Funne Louis to Centerville, then turns west and crosses Little river a little below Gilmore's ferry. On the Colfax-Winnfield road the high Grand Gulf hills are encountered just south of Saddle bayou. About two miles northwest of Colfax there is a very good outcrop of Grand Gulf sandstone in Rocky ford. The sandstone is quite abundant as far north as Sec. 19, 7 N,, 3 W. Around Lena are large quarries in the Grand Gulf rocks. Hilgard reports these beds as capping the elevated ridges about Cloutierville on Red river.* The next notable Exposure *Am. Jour. Sci., 2d Series, vol. 48, 1869, p. 337. II] General Geology : Grand Gulf Oligocene 97 of Grand Gulf is in the Kisatchie hills. The road from Lees- ville to Provencal passes through a strip of black prairie land about four miles from Leesville called Anacaco prairie. Cal- careous concretions are scattered over the ground in large numbers but no fossils were seen. Another small calcareous prairie of about four acres in extent occurs north of Hardshell. In about Sec. 5, 4 N., 8 W., a light colored ledge crops out in the road. Between Kisatchie bayou and Bellewood, sandstone becomes quite common, and calcareous prairies are still to be found. The northern limit of the sandstone is about Bellewood. On the divide between the headwaters of Kisatchie and Toro bayous the Grand Gulf probably extends well to the north, and it may be that the "Bad Hill* " mentioned by Hopkins as seven miles south of Many is in this region. If Bad Hill is seven miles due south of Many it is Lower Claiborne, for numerous fossils are found in this region and the distance to the first Grand Gulf outcrop due south of Man}- is about 18 miles. The writers have in no place seen the Grand Gulf north or west of Bayou Toro. The large quarries in 4 N., 11 W., which have been opened to obtain stone for crib work at Sabine Pass, Texas afford good opportunities for examining the formation in this region. The line of parting between the Grand Gulf and the Jackson lies from a mile to two miles east of Bayou Toro from the railroad bridge to its mouth, where the Grand Gulf crosses the Sabine river into Texas. In Sec. 9 and 1 7 3 N. , 11 W. , large quantities of stone are strewn over the hillsides. Great masses separated by erosion often occupy outlying hills and are locally supposed to be of volcanic origin. Of the southern boundary of the formation Hilgard says : ' ' The line originally laid down by me, and adopted by Prof. Hopkins, in his Geological Map of the State, is based upon the connection of the outcrops near Chicotville, then near the mouth of Mill creek into Calcasieu river and the point on the Sabine (Salem) given as the limit between the Quaternary and Tertiary, by Prof. Buckley of Texas. "§ In the bed of the Nez Pique and Boggy bayous Hilgard found, what he * 1st Annual Report. La. Geol. Surv., 1870, p. 99. |Supl. and Final Rept. of a Geol. Recon. of the State of Louisiana, 1873, p. 16. G 98 Geological Survey of Louisiana [Sect. considered, characteristic outcrops of the materials of the Grand Gulf group, viz. ; solid greenish clays and jagged claj^ sandstones. East of the Mississippi Hopkins has mapped as Grand Gulf almost all the hill-lands of the Florida parishes. The Grand Gulf is here deeply covered with deposits of Lafayette material, and exposures have been noted in but few places. Hilgard reports the Grand Gulf along the river front as far south as Tunica bend.* Two miles northeast of Laurel Hill McGee found an exposure of Grand Gulf in the west fork of Thomp- son's creek. t So far as we know these are the only exposures of Grand Gulf which have been reported, in Louisiana, east of the Mississippi ; indeed, Clendenin states that the Mississippi is the only stream which has succeeded in cutting through the Lafayette and exposing the underlying Grand Gulf. Thickness. — Hopkins calculates the thickness of the Grand Gulf in the vicinity of Harrisonburg at 182 feet and remarks that this is probably less than the true thickness of the deposit.;}; Some of the hills on Bayou Toro are barometrically^ from 250 to 300 feet high and hence we feel quite safe in assuming for the Grand Gulf a thickness of at least 300 feet. Fossils — These beds have not yet yielded, in Louisiana, any trace of animal remains. Specimens of silicified wood have been found at a number of places, 1| and beds containing twigs and leaves have also been reported. Veatch has obtained verj^ good impressions of leaves about two miles west of Hornbeck. Specimens of silicified palm-wood collected by Johnson in Rapides parish have been identified by Knowlton as Palmoxylon quens- tedtizw^ P.cellulosiim. Johnson called them Pliocene; McGee says they are of Grand Gulf age ; Knowlton thinks the age very uncertain. § Age of the Grand Gulf Results of work in Alabama and Florida. — It thus appears that no clue to the age of the Grand Gulf is given by the Louisiana * Am. Jour. Sci. 3d Series, vol. i, 1871, p. 236. t 12 An. Rept. U. S. Geol. Surv. part I, p. 432. X 2d An. Rept. La. GeoL Surv., 1871, p. 19. II Hopkins ist An. Rept. La. GeoL Surv., 1870, p. 100. § Proc. U. S. NaL Mus., voL 11, pp. 89-91, pL 30, 1888. Iij General Geology : Lafayette 99 deposits. The material which has been lumped together, in Louisiana, as Grand Gulf lies between the Vicksburg (Lower Oligocene) and the upper Pliocene. It may therefore represent Upper Oligocene, Miocene or Pliocene. In Mississippi the conditions are a little more satisfactory. The collections of Johnson at Vernal P. O. demonstrated that the upper part of Hilgard's Grand Gulf, in that region, is Chesepeake Miocene. But the Alabama and Florida sections were needed to show the age of the Grand Gulf proper.* It has there been shown that the typical Grand Gulf passes under the Oak Grove beds, and hence is probabh- equivalent to the Chatahoochie or Upper Oligocene beds. The Grand Gulf beds above the typical Grand Gulf and below the Pascagoula clays pass into the Oak Grove sands, which are now regarded bj'^ Dall as transitional between the Oligocene and Miocene, j LAFAYETTE! Historical Origin of the Term Lafayette The attention of geologists engaged in work on the southern coastal plain was earl)^ attracted by beds of brightly colored sands and gravels extending over wide areas. The color of these deposits soon suggested a name ; they were called "Orange Sand" by Safford in 1856 ||. Hilgard adopted the term in his Mississippi report and gave the most complete description of the deposits that has been made up to the time of McGee's * Smith, Geol. Surv. Ala., 1894, pp. 104-107 ; Dall and Stanley-Brown Bull. Geol. Soc. Am., vol. 5, p. 164, 1894. f A Table of North American Tertiary Horizons, Correlated with One Another and with Those of the Western Europe, with Annotations by Wm. H. Dall, 18th An. Rept. U. S. Geol. Surv., 1896-97, Part II, p. 340^ 1898. :}: See article by W J McGee. — The Lafayette Formation, 12th Ann. Rept. U. S. Geol. Surv., 1891, pp. 347-521, which is by far the most complete account of the subject yet published. II Geol. Recon. of Tenn. by J. M. Safford, 1856, pp. 14S-162. Quoted by McGee. loo Geological Survey of Louisiana [Sect. report in the 12th Aunual of the United States Geological Survey. Safford referred the Orange Sand to the Cretaceous, to which only a portion of his deposits belonged, but later called it Ter- tiary and proposed a new name the " Bluff Gravel" for the por- tion which was of presumably Quarternary age*. Hilgard maintained that the deposit was of Quarternary age and was a southern equivalent of the northern drift. He supposed that the deposit originated in the great floods of water issuing from the ice front. This idea has given rise to the names "Drift," "southern Drift" and "Stratified Drift" which have been applied to this formation. The uncertain meaning of the term Orange Sand caused the adoption in 1891 of the term Lafayette formation, from the typical localit}^ in Lafayette county, Mississippi where Hilgard first studied and named the formation. The opinion now gener- ally held is that the Lafayette is a littoral or coastal deposit of late Pliocene age and hence anterior to the glacial period. It has no connection whatever with the great sheets of true drift or till brought down by the glaciers. Features of the Formation in Louisiana Definitive Features of the Deposits In Louisiana the onl}^ criterion for the determination of the beds of this formation seems to be the chert and quartz pebbles, often with casts of Paleozoic fossils, which portions of the beds contain. The lithological resemblance of the sands of this formation to the \teathered sands of the underlying deposits is so close that it is impossible to differentiate them. This resem- blance has led to many incorrect references of red sandy mater- ial to the Lafayette. Thus, Hopkins refers the iron bearing sandstone common around Rocky Mount and in all the higher hills of northern Bossier, Claiborne, Jackson and Union parishes to the Drift. Harris has collected Lower Claiborne fossils in the Rocky Mount material and is inclined to regard the fossils as being in situ. Veatch has obtained a series of very perfect * Geol. of Tenn., 1869, pp. 432-433. • 11] General Geology : Lafayette ioi casts, preserving to an extreme degree all the fine surface sculp- turing of the shells, from very coarse ferruginous sandstone about nine miles west of Ruston. lycrch seems to have made an error in his first report* where he refers the red sands and sandy clays, which form so large a part of the surface of northern Louisiana, to the Lafayette. Vaughan has shown, and the observations of the present survey support his conclusions, that the red sands are in part, at least, Lower Claiborne. f Distribution of the Gravels The observations in the State have not yet been sufficient to show clearly the minor features of the distribution of gravels ; but the main localities are known. East of the Mississippi. — In the hill lands, east of the Mississippi river the gravel is very well developed. It there overlies the Grand Gulf beds and seems to pass under the Port Hudson. Regarding the distribution of the gravel in the Florida parishes Hopkins says: In "Washington Parish the pebbles are common. About five miles east of the Tangipahoa these have disappeared and the deposit is a yellow clay, with fragments of brown hematite and red ochre. On Beaver creek, and to the west of Tangipahoa, it has changed to a coherent sand of an intense red color. Red and yellow clay again, with a few quartz pebbles, are seen on the road to Greensburg, and red sand at that place. Violet and yellow clay with a peculiar chocolate shale, are found between this point and the Amite river. Then the pebbles recommence and are fossiliferous as usual. Clinton and Jackson are built upon them. They under- lie the bluff to within a mile of the river at Bayou Sara. J The southernmost point on the Mississippi at which Lafayette gravels have been found is reported by McGee as in a road cut " seven or eight miles south-southeast of Bayou Sara, a mile west of Thompson's bayou, and midway between Fairview and Star Hill plantation. § *Bull. La. State Expt. Stations : Geol. and Agr. part I, pp. 24-26, 1892. t BulL U. S. GeoL Surv. No. 142, 1S96, pp. 20-22, i8q6. :): Second Annual Report GeoL Surv., La., 1871, p. 22. ^ Twelfth Annual Report U. S. Geol. Surv. p. 430. I02 Geological Survey of Louisiana [Sect. Along the northern and southern borders of the Grand Gulf. — West of the Mississippi the gravel is reported well developed on both the northern and southern borders of the Grand Gulf. Clendenin reports a very extensive gravel pit in the hills of southern Rapides, east of the Kansas City, Watkins and Gulf railroad where large quantities of gravel are obtained for rail- road ballast.* According to Hopkins it is quite common between Cheneyville and the lime kiln near Bayou Chicot. f Gravel is extremely abundant along the Iron Mountain Railroad from Alexandria as far north as the northern boundary of the Grand Gulf, where it suddenly ceases. All along the northern line of the Grand Gulf, gravel seems to be quite abundant. It has been reported by Hopkins from the Harrisonburg hills. J It has been seen by the junior author on the northern edge of the Grand Gulf just south of Saddle bayou on the eastern road from Colfax to Winnfield ; in the Kisatchie hills ; and in the hills south of Toro bayou along the K. C. P. and G. R. R. Aronnd Many and Sabinetown. — North of the last locality referred to above is a great stretch of country covered with fossiliferous Jackson and Lower Claiborne. On the railroad, the first place where gravels are exposed north of the Grand Gulf territory is about two miles south of Many on about the line of parting between the Lower Claiborne and the Lignitic. Going west from Many no gravel is seen until the vicinit}- of Sabinetown is reached. The gravel caps the first big bluff on the east side of the river above Sabinetown and on the top of Sabinetown bluff is extremely well developed. The top of the bluff at Pendletown is covered with extremely red sand but no gravel was seen in it. x\t the mouth of Bayou Negreet Harris found a pebble conglomerate containing Lower Claiborne fossils. The fossils were poorly preserved and may have been redeposited. The Black lake bayou gravel train. — In the northern part of the state the gravel is almost entirely confined to the two great gravel trains which were first pointed out by Lerch. *Bull. La. State Exp. Sta; GeoL and Agr., part III, 1S96, p. 214. f 2d Ann. Rept. GeoL Surv. p. 22. First Annual Rept. La. GeoL .Surv., 1870, pp. 99, 102. II] General Geology : Lafayette 103 The most important and continuous is the Black lake bayou and Dauchite bayou deposit. Between Shongaloo and Sykes ferry the gravel is quite abundant. At old Haynesville great quanti- ties crop out in the hillsides. The territory between the two localities was not passed over, but it seems probable that the two deposits are connected. Going south the gravel ridge narrows. No northern gravels are found on the red lands in T. 21 N., R. 9 W. At Minden gravel was seen from about half a mile west of the Dauchite bridge to a little beyond Crow's bayou on the Homer road. On the large hill between Minden and the bridge it is common to a height of 65 feet above the bottoms. Between Minden and Sibley nearly all the hillsides show gravel. In the railroad cut at the latter place 17 feet of gravel and cross- bedded sands are exposed. Pebbles as large as a man's fist are seen here. This gravel was found as far east as Black lake bayou. The country between Sibley and King's salt works was not personally examined, but we are credibly informed that gravel is common. Pebble conglomerate is often seen on the hills around King's salt works, and on the Sparta-Campti road betw^een Castor and Toby creeks. Just south of this exposure is a very fossiliferous Lower Claiborne prairie and no more gravel occurs between here and Lake village. On the west side of Black lake bayou, between Lake village and Coushatta, the gravel band is three or four miles wide. At Black lake the gravel again occurs on the eastern side of the bayou. Here it is in close proximity to fossiliferous Lower Claiborne prairies. The gravel occurs on the hillsides in Sec. 4, 11 N., 6 W. The very crest of the hill is covered with Osterea falciformis and O. johnsoni. At Grand Ecore ten feet of white and yellow chert pebbles and sand cap the bluflf. Thej^ extend scarcely an eighth of a mile from the river. Saint Maurice and Montgomery . — At Saint Maurice large quartz boulders are found on the hillsides twenty to forty feet above the fossiliferous Lower Claiborne in the bed of Saline bayou. From 3 to 4 miles northeast of Montgomery, on the east side of Bayou Nantaches, there are quite prominent escarpments of I04 Geological Survey of Louisiana [Sect. sandstone which in turn are overlaid by beds of white quartz gravel and conglomerate. Above the gravel are from 50 to 75 feet of yellow and white sands. Ouachita river gravel train. — The gravel train along the Ouachita is not nearlj^ so extensive. It is reported from about 12 miles south of Monroe. About three miles north, on Col. Jones' stock farm, there is a large gravel pit which is of great local importance. Gravel is seen along the railroad for two miles west of Monroe. A prolongation of the same deposit appears in force at the bluff about a mile above the mouth of the D'Arbonne and at Ouachita city. At Ouachita city the gravel band is about three miles wide. In noriher^i Union and Claiborne. — Gravel localities are sprink- led all over the northern part of Union and northern Claiborne. The following localities may be mentioned : near L'Outre bridge on the Spearsville-Ouachita city road ; south of Cherry Ridge ; around Farmersville and as far south as the D'Arbonne ; on the hills west of Corney ferry, three or four miles from Farmersville ; at the Corney bridge on the Junction city-Lisbon road ; on the hills on the south side of Middle Fork bottoms near Colquett bridge ; and between Colquett and Gordon in occasional patches. Around the Cretaceous outcrops. — Besides these localities sev- eral of the so-called Cretaceous outcrops show gravel deposits, viz. : Rayburn's salt works and the Five Islands. For information on the gravel of the Five Islands see special report. Localities %vhere the gravels are found in wells. — Besides these surface outcrops wells have in several places revealed the pres- ence of beds of sands and gravel which presumably belong to this formation. A bed of gravel from 20 to 40 feet thick seems to underlie the Red river valley in the vicinity of Shreveport at a depth of from 50 to 80 feet. Hopkins reports gravel under the Avoyelles prairie at a depth of 40 feet. In nearly all the Port Hudson territory deep wells reach the Lafayette gravels. Regions with no Gravel Four principal regions in which no gravel has been observed may be thus outlined : (i) The alluvial lands ; (2) the country overlaid by the Port Hudson ; (3) an area centrally located II] General Geology : Lafayette 105 between the Red, the Ouachita and the State line including Caldwell, the major part of Winn, Jackson, eastern Bienville, southeastern Claiborne, the major part of Lincoln and the west- ern part of Ouachita parishes ; (4) all the territor)^ lying west of the Black lake gravel train and north of the Grand Gulf except the area about Many and Sabinetown. Thickness of the Deposit In northern Louisiana exposures of a greater thickness than 10 or 20 feet seem to be rather rare. In the region of Minden the deposit is at least 60 or 70 feet thick. In southern Louisi- ana it shows a thickness in the Lake Charles wells of from 150 to over 200 feet. On Cote Carline, Grande Cote and Belle Isle the borings show that a thickness of 200 feet is by no means uncommon. Hole No. 7 on Cote Carline, which is for the most part in material of presumably Lafayette age, is 442 feet deep. On Belle Isle 400 feet of sand is recorded in hole No. 2. Conclusions There can be little question that these deposits were all formed in the same way and that they represent shore deposits. There does seem, however, to be room for a reasonable doubt that they were formed at the same time. It is seen in the beginning that the argument for the unity of a deposit which is differenti- ated from other deposits merely by the presence or absence of chert and quartz gravel is not very strong. Hilgard noticed the very peculiar irregularity of the distribution of the gravel in Mississippi and the same has since been found true in Alabama. In Alabama gravel occurs to a very limited extent or not at all (i) over the territory of the Rotten limestone, (2) over the Black bluff or basal Lignitic and (3) over parts of the Jackson or white Limestone.* In Mississippi it is found to a very limited extent (i) over the territory of the Jackson, being entirely absent in the prairies ; (2) it is wanting in large portions of the territory occupied by the Rotten Limestone of the Cretaceous (3) in the Flatwoods region [Midway] of the northeastern part of the State t- This absence of the gravel from the most calcareous *Geol. Surv. Ala., 1894, p. 68. fMiss. Rept., i860, p. 5. io6 Geological Survp:y of Louisiana [Sect. deep-sea deposits seems hardly well explained by the theory of the common time origin of these deposits. The Arkansas Orange Sand or Lafayette as identified by McGee seems capable of division. Harris found a portion of the pebble beds passing beneath the Midway Eocene in the vicinity of Little Rock. The Plateau Gravels of Hill contain Cretaceous fossils in Clark county, and Harris is inclined to regard the fossils as of the same age as the gravel. Too little is known of the gravels of Louisiana to justify any very conclusive statements, and many years must elapse before the problem can be fully worked out, but the facts we know at present seem to suggest at least a working hypothesis. The band of pebbles which appears along the southern edge of the Grand Gulf seems to pass beneath the Port Hudson and to be the gravel which is struck in deep wells sunk in the Port Hud- son territory. It is the time equivalent of the Lafayette of McGee. The band of gravel which follows the escarpment which marks the northern limit of the Grand Gulf does not extend, to any appreciable extent, over the adjacent lower territory of the Jackson.* The question then becomes, has the time since the deposition of the Lafayette been sufficient for the erosion of a strip of gravel several miles wide along a course which cuts the principal streams at right angles? The gravel train in the vicinity of Monroe lies in about the position and direction of the shore line in the Jackson period. The gravel at Many andSabinetownis in about the position of the Claiborne shore-line. The Black lake bayou gravel train occupies a questionable position. Much of it lies along a line between the Lignitic and Lower Claiborne but seems too far east to represent the Claiborne shore-line. Indeed if the gravel in Sec. 4, 11 N., 6 W., be considered a part of it, it is younger than the Claiborne. We are hardly prepared to affirm that this is a true explanation of the deposition of the gravel as the facts at hand are entirely * Hopkins, ist Annual Rept. La. GeoL .Surv., p. 104, says : " The inter- vening region of the Jackson and Vicksburg is lower ; and often entirely bare of drift as is the case with marly regions of the Grand Gulf." When- ever the northern edge of the Grand Gulf was passed by the present writers no gravel was observed even on the Jackson. II] General Geology : Quaternary 107 too meagre to justify such a statement. But it is felt that as the stratigraphy of the Southern states is more carefully worked out the positions of some of the gravel beds, which now seem ver}^ strange will become quite clear, and that parts of them will be found to be the true equivalents of adjoining fossiliferous beds. QUATERNARY Classification HlSTORICAI, The literature on the Quaternary deposits of Louisiana is quite voluminous. The great river and its delta have been studied and written about since the first settlement of the country. Commerce demanded it ; and the scientific man found in the river and flood plain, problems of ver}- great interest. Some of these problems are so large and the observed data so small that our present knowledge is by no means satisfactory. Their elucida- tion will require some years of very careful hard work. Lyell. — Passing over the earlj- observations of the U. S. Engineers engaged in work on the river and of the earlier unpublished part of the work of Forshey and Riddel we come to Sir Charles Lyell. The visit of this great geologist, and his subsequent publications may be considered the beginning of the present study of the river deposits. He conceived for the alluvial deposits a thickness of at least 500 feet and on this based his calculation of 67,000 j^ears as the age of the delta. He recognized the loess, and at Port Hudson saw deposits which he considered to be of alluvial formation.^ Hilgard.— \n\ns Mississippi Report, i860, Hilgard proposed the name Coast Pliocene for a series of recent, partly cypress swamp, partly marine beds with recent shells, occupjnng a strip along the Gulf Coast from 12 to 20 miles wide. This has its homologue along the whole southern coast of Louisiana. In the same report he recognized and named the Yellow Loam.f * Second visit to the United States, 3d Ed., 1855, p. 250 ; also Principles of Geology, nth Ed., p. 455. f Report on the Geology and Agriculture of the State of Mississippi, i860, p. 197. io8 Geological Survey of Louisiana [Sect. After his examination of Port Hudson and his trip through southern lyouisiana he recognized over the whole area the equiva- lents of his Coast Pilocene, and proposed for the whole the name Port Hudson group.* The layer of blue clayf which the labors of Humphreys and Abbott had revealed to be very widespread in the bottoms, and which they referred to a number of different geological horizons, from the Cretaceous up, Hilgard referred to the Port Hudson. J He came to the conclusion that the present deposits of the river are of inconsiderable thickness ; a view which he has maintained in all his subsequent writings. Johnso7i. — Investigations by Mr. I,. C. Johnson in 1890, in southern Mississippi and in the region north of lyake Pontchar- train, in the coastal phase of the Port Hudson, led him to pro- pose for it the name Pontchartrain clays. § At the same time he proposed the name Biloxi sands for the more recent coastal formations. The difficulty in distinguishing between the two beds, which were formed under very similar conditions, led to the extension of the meaning of Biloxi sands to include the Pontchartrain clays. || McGee. — In his correlation of the coastal deposits McGee includes all the Quaternary deposits in Louisiana, except the most recent alluvium, under the Columbia formation.^ He restricts the Orange Sand, as used by Safford in i888,ff to the basal portions of the Yellew Loam. *Am. Jour. Sci., 2d series, vol. 48. p. 332, 1S69. t Hydraulics and Physics of the Mississippi River, p. 99. XK-xn. Jour. Sci., 3d series, vol. 47, p. 79 ; also Am. Jour. Sci., 3d series, vol. 2, pp 391-404; Am. Assoc. Adv. Sci., Proc.,vol. 20, pp. 222-236. § BuH. Geol. Soc. Am., vol. 2, pp 20-25, 1890. II Geol. Surv. Ala., 1894, p. 41. Tf The Lafayette formation by W J McGee, 12th Annual Report U.S. Geol. Surv., Part I, p. 392. ff Agricultural and Geological Map of Tennessee (J. M. Safford, State Geologist), 1888. 11] General Geology : Quaternary 109 TABLE OF LOUISIANA QUATERNARY FORMATIONS River Development Costal Development Alluvium Coastal Marshes Biloxi Sands Yellow Loam Loess I Pq1„_, f Chocolate Colored Loam ~| g-, • Fluviatile Port Hudson I ,. ' j Yellow Loam I c'^^fic or Old Alluvium [ /Moa^.-^ "i Ponchartrain Clays or [- ,^ , ^ Basal Gravel j ^mci^ee; | Marine Port Hudson pJ°^°. L Coast Pliocene (Hilgard) J ^°°^ DEVEIvOPMENT AND CHARACTERISTICS OF LOUIS- IANA QUATERNARY FORMATION MANNER OF FORMATION Natural periods in the Quaternary of Louisiana. — The history of the Eouisiana Quaternary seems to be divisible into three parts : a long period of deposition, with varying conditions in altitude and consequent differences in the character of sediment deposited ; a period of erosion ; and the present, comparatively recent period of deposition. First period of stibsidence. — In the beginning of this period the land must have stood over 248 feet* higher in the northern part of lyousiana than it does to-day. In the valley where the stream was sufficiently rapid, portions of the lyafayette gravels were re-deposited or other gravel brought down by the river from the north. The deposition of gravel would naturally be greatest in the upper part of the valley while nearer the coast the material would be finer. Along the coast, deposits of clay and sand would be formed, which near the mouth of the river they would contain Rangia and other brackish water molluscs, while at a distance from the main outlet of the river the deposits would contain recent marine species. As the subsidence progressed the deposi- * The depth of the Quaternary deposits at Lake Providence. — Hilgard and Hopkins, Report on Borings between Memphis and Vicksburg, 48th Cong., 1st Sess., House Ex. Doc, vol. 19, 1884, p. 481. no Geological Survky of Louisiana [Sect. tion of saud and gravel in the main valle}' would cease and their place be taken by fine cypress swamp clays. In these cypress swamp clays local beds of sand and loam were formed along the sluggish streams which meander aimlessly through the valley. In the Mississippi valley the irregular melting of the glaciers which occupied the whole region north of the Ohio and Missouri rivers caused great floods which brought with them large quan- tities of glacial rock meal. At times this flood may even have overflowed the bounding hills or bluffs of the old valley and formed on their summits great natural levees of silt even as the pigmy Mississippi does to-day. At any rate these periodical floods, caused by variations in temperature along the ice front, must have formed extensive mud flats, as wide as the river valley, and winds blowing over them would experience no diflS- culty in transporting this impalpable silt to the summits of the bordering hills. Period of elevation. — At the close of this subsidence in which the land reached a level a hundred feet* lower than to-day, a period of elevation commenced. During this time an eleva- tion slightly above the present was reached and the river cut out the deposits of the preceding period. The amount of this excavation can be judged by the height of the Port Hud- son bluffs and the Opelousas, Carrencro and Cte Gelee hills. To this is to be added the ver}' inconsiderable depth of the older material below the present alluvium. In the upper Red river valley, this excavation amounted to about 60 feet. Present period of szibsidence. — At the close of this elevation the present period of subsidence commenced and with it the deposi- tion of the alluvium. That a subsidence is going on is evidenced by a number of facts : (i) by the drowned condition of the mouths of the majority of coastal rivers ; (2) by the *If the yellow loam and the Icess are not considered, a subsidence of this amount seems to be quite capable of producing the deposits observed in the Mississippi valley. The origin of the loess is so little understood that an assumption that the subsidence was equal to the height of the highest loess above sea level seems hardly well founded. If the subsidence was so great, about 500 feet, as the estiiarian theory of the origin of loess demands, we should find well marked marine forms at Baton Rouge and Port Hudson. II] General Geology : Quaternary i i i burial of Indian shell heaps and mounds with recent material as at Belle Isle and in man\- mounds along the Mississippi coast ;* (3) by the formation of numerous long dune-shaped islands just off the coast and along the seaward margin of the coastal marshes which are features of a subsiding coast ; f (4) by the observations of Maj. Ouinn, U. S. E., who reported the extra- ordinary subsidence of one foot between 1875 and 1894;;}: (5) from the almost stationary condition of the mouths of the Mississippi. The Basal Gravel § Cha7-acteristics and development. — The basal portions of the Quaternary which were formed by the redeposition of some of the preceding gravel have been definitel)' recognized in but tw^o localities in the State because of the difficulty in separating them from the underlying Lafayette. In the Lake Providence bor- ings there are certain beds which Hilgard is inclined to regard as basal Port Hudson. || McGee reports the basal gravel 7 or 8 miles south-southeast of Bayou Sara and in the region between Bayou Sara and the state line.^* He also states that the basal gravel was found in the New Orleans well and below the Cal- casieu prairie, a statement which seems to require further proof. The low level Red river gravels, which have been provisionally referred to the Lafayette, may belong to this period. The Port Hudson Origin of Term. — In the American Journal of Science for November, 1869, Hilgard proposed the name Port Hudson for a group of swamp, estuarine, bayou and marine claj's and sands covering parts of Louisiana and Mississippi. The formation * Geol. Surv. Ala., 1894, pp. 45-46. f Eastern Sea Coast Marshes by N. S. Shaler, 6th Ann. Rept. U. S. Geol. Sur., 1885, p. 360 ; also W J McGee, Gulf of Mexico as a Measure of Isos- tacy. Am. Jour. Sci., vol. 44. p. 187. :{: Quoted in Annual Cyclopaedia for 1895, Appleton and Co., p. 427. We have not been able to find this statement in the Annual Reports of the Chief of Engineers from which it seems to have been taken. II 48th Cong. House Ex. Doc, vol. 19, 1884, p. 480. § McGee, 12th An. Rep. U. S. Geol. Sur., part i, p. 499. ** I2th An. Rep. U. S. Geol. Sur., part i, pp. 430-431. 112 Geological Survey of Loulsiana [Sect. was named from Port Hudson, Louisiana, where the typical exposure is found. General characteristics. — This formation consists of beds of dark colored clays, commonly blue, black or green but some- times gray and yellow, containing calcareous concretions and occasional beds of gray sand and slit. The blue clay which is probably the most distinctive bed commonly contains stumps and trunks of cypress and other lowland trees. It shows two very distinct facies : a marine and fresh water. Along the gulf coast the littoral portion of the formation com- monly contains marine and, near the old coast line, brackish water shells. The river portions contain cypress stumps, driftwood and occasional fresh water shells. Synonymy. — This development of marine facies has given rise to two very different meanings for the term Port Hudson. In the river where the Port Hudson is strongly differentiated by physical characters from the loess and yellow loam and separated from the very similar recent deposits by an erosion interval, the term Port Hudson is restricted to a fairly limited group of clays at the base of the Quaternary series. On the coast where depo- sition has been going on continuously and where the deposits of to-day are forming under the same conditions and contain the same marine forms as the earlier Quaternary beds, it is impossible to distinguish between them. This has led Hilgard to uncon- sciously use the term Port Hudson in the costal region to cover everything except the recent sea marsh deposits. That is, in the the costal region the Port Hudson not only includes the equiv- alents of the Port Hudson of the valley but the marine equiv- alents of the loess, the yellow loam and in all probabilit}^ a part of the alluvium. The Port Hudson bluff, which is the typical exposure for the formation, represents only the fluviatile development. This led Johnson in 1890* to propose the name Pontchartrain clays for for the marine equivalents of the Port Hudson. The Pontchar- trian clays consist of brownish or yellowish blue clay with sand partings, and contains a few stumps and marine shells. At the * Bull. Geol. Soc. Am., vol. 2, pp. 20-25, and Am. Jour. Sci., vol. 40, pp. 332-333. 1890. I] General Geology: Quaternary 113 same time the term Biloxi sand was suggested for the recent costal formations, in general equivalent to the recent alluvium of the river. It was found impossible to differentiate them in the field and in 1894 the Pontchartrain clays and Biloxi sands were all included under one head, the Biloxi sands.* The difficulty, nay impossibility, of distinguishing between the different parts of the Quaternary in the coastal region has given rise to a very interesting discussion on the thickness of the recent alluvium in the delta below New Orleans. This seems to be one of those points where a person can take either side and prove that he is right. If the period of the recent alluvium be said to begin at the time when the cutting out of the Port Hudson and loess deposited in the valley commenced, then the delta formed of this material would be composed of redeposited Port Hudson material with marine shells and exactly the same difficulties will be experienced in differentiating the two deposits that are experienced both east and west of the delta region. If the period of the recent alluvium be defined as com- mencing when the period of degredation ceased, the same difficulties will be experienced. Off the delta to day marine beds are forming which are the time equivalents of the recent alluvium, but which are in everyway similar to those which formed under similar conditions in the Port Hudson period proper. Indeed criteria for the separation of the Port Hudson proper from the more recent deposits in the lower delta region seem to be entirely lacking. All our present knowledge seems to justify, is to lump the whole together as has been done east of of the Mississippi in the Biloxi sands and west of the Mississippi in the Port Hud.son. Areal distribution and topographical features. — These vast beds of clay, which have not been exposed long enough for the development of drainage systems and which from their clayey nature prevent a perfect subterranean drainage, have had a very marked effect on the topography of part of Louisiana. East of the Mississippi they have given rise to the " Pine flats" or "Pine meadows" lying between the pine hills and the coastal marshes. West of the Mississippi they have produced another *Geol. Surv. Ala., 1894, p. 41. H 114 Geological Survey of Louisiana [Sect. series of pine flats in Calcasieu parish and the whole prairie region of southern Louisiana (see geological map). The post oak or upland flats of Red river valley seem to belong to the same age also. The Port Hudson seems to be distributed over the whole lower Mississippi valle}- at a slight depth below the modern river deposits. In places through the river valley the Port Hudson appears to be represented b}' butte-like masses which were not completely eroded during the degredation period that followed their deposition. The Moorehouse hills seem to represent one of these erosion-formed masses of Port Hudson material. The Bayou Macon hills represent hills of the same type which have received a coating of j^ellow loam. Further down the valley another one of these outliers is found in the Avoyelles prairie. Thickness of the Port Hudson. — The deposition of the Port Hudson on the irregular and probably steeph' inclined surface of the Lafayette gives to the Port Hudson a decidedly varying thickness. The wells about Lake Charles seem to indicate for the formation an average thickness of a little less than 200 feet. The great thickness, 354 feet, observed in the Kirkman well near Lake Charles appears to be rather abnormal. In the Mississippi valley at Lake Providence there are 205 feet of Port Hudson under 42 feet of recent alluvium.* East of the river the work of the Alabama survey has revealed the total thickness of the Quaternary to be from 200 to 250 feet.f Of this from 10 to 100 feet is supposed to be recent and the balance Port Hudson proper. The New Orleans well had not passed through the Quaternary deposits at a depth of 630 feet- In Red river valley in the vicinity of Shreveport the Port Hudson is about 100 feet thick. This would seem to allow for the Port Hudson a river- ward development of from 100 to 200 feet, a normal coastal development of 200 feet and an extreme development immedi- ately on the coast of over 600 feet. Fossils. — The most common fossils are plants ; leaves, trunks of trees and roots occuring in many parts of the formation. Vertebrate remains have been found in numerous parts of the ^Hilgard 48th Cong, ist Sess., House Ex. Doc, vol. 19, p. 493. t Geol. Surv. Ala., 1894, p. 43. 11] General Geology: Quaternary 115 State in deposits which are the time equivalents of the upper part of the Port Hudson or the lower part of the loess. The early accounts of the geology of the State contain reports of find- ing mastodon remains near Opelousas. Carpenter reports the find of a mastodon jaw and teeth and the tooth of a large horse on Bayou Sara in the parish of West Feliciana. f The bone beds on the Mississippi just north of the line are extremely rich. On Petite Anse the remains of Mastodon, Mylodoii, Equus and Elephas have been reported. Mastodon bones have been reported from Port Hudson bluifj ; from Cote Blanche §; from King's salt works; Price's salt works|| : Rayburn's salt works|| ; Dunbar's creek, West Feliciana parish; and at Alsworth's, 6 miles above Baton Rouge •". In the river exposures fresh water shells are occasionalh' found and Hilgard has reported imperfect specimens from Cote Blanche and Petite Anse**. Marine forms are found over nearly the whole of the area covered by the marine phase of the Port Hudson. They have been reported \>y locality from Baj-ou Sale, Belle Isle, Opelousas, Lake Charles, Bonnet Carre on the Mississippi river above New Orleans, New Orleans, the Lake Borgne bor- ings and Pontchatoula. The Lcess and Yei;;>iiii; z:2sssi:asss^ ,---:ri^/>!.t GKOLOGIC.M. t^URVKY OF LOUISIANA, REPORT, 1899 A R K A X S A S R 16 W „-J R 15 W "^J^f^^^i^ R 14 W .l/ii/> 0/ .Woilhern Caddo parish in iSjo- Compiled from Public land Siittfys By a. C. Veatch ^11] Shreveport Area : The Raft 169 a time the tops of the dead trees were broken off by the winds, leaving the unsightly stumps as silent witnesses of the great catastrophe. A peculiar ox-bow shaped depression, being below the level of the banks of the river at the mouth of Twelve Mile bayou was filled with water at the same time forming Clear lake. Origin of Black bayou swamp. — The Black bayou stream valley being higher than the Cypress bayou stream valley was not so deeply inundated by the daming of Twelve Mile bayou. Still it was low enough * to receive a little water. Cypress trees, being fitted by their peculiar knees to grow in such a situation, soon converted the land into a cypress swamp. Formation of Silver lake and Poslo?i's lake. — Silver lake and Poston's lake were formed in the same way, the first in a stream valley the second in a bottom-basin, but at a later date. Poston's lake is shown on the land office charts made in 1839, when the raft was far below its outlet, as a bayou. On Woodruff's map of 1872 it is a large lake offering a good steamboat passage. It is now a bayou. Thus in fifty years a lake large enough for the passage of large steamboats has been formed and destroyed. Outlet bayous — The formation of the outlet bayous, both arti- ficial and natural, has already been discussed. It only remains to call attention to the development of the drainage systems by outlet bayous. A reference to the two maps accompanying this report will show something of this development. It will be noticed that in the lower part of Old Red bayou the outlet channels, Dooley's, Cowhide and Horseshoe, have delib- erately cut across the old channel. Indeed the map seems to indicate that Trinity bayou and the lower part of Cottonwood bayou represent the true continuation of Old Red bayou, and that the portion of Old Red baj'ou, so called which flows west, is really a continuation of the Peach Orchard outlet. * The average elevation of the river banks about Shreveport is about 170 feet above Gulf level. The bottom of Black bayou where crossed by the Kansas City, Pittsburg and the Gulf Railroad is, according to the railroad companies corrected levels 173 feet. Thus the lower part of the valley would probably receive a few inches of water and even if the water did not back up into the valley the current would be so checked that the lower part of the valley would be very imperfectly drained. 170 Geological Survey of Louisiana [Sect. Most of the outlets were made before any of the land surveys, and we have a record of the formation of one of them only. In 1841 Lieut. Col. Long says: " Commencing at the southern boundary of Arkansas and proceeding downwards, we have in succession the following considerable outlets from the main river, communicating more or less directly with Caddo, or Sodo lake, situated on the southwest or right side of the valley, viz.: Red bayou, which is the uppermost of all the bayous within the district just mentioned; New bayou, Dooly's bayou, and Chef- tel's bayou, besides several others of inferior size. The three bayous first mentioned are situated above the head of the raft ; while the last passes from the river at a point about midway of the new or present raft. One of these outlets, viz.: New bayou, has been formed during the existence of the present raft."* Sedimentatio7i . — One of the most important changes wrought by the raft was the building up of the land by sedimentation. The checking of the current by the raft, the large stretches of almost dead water both in the river and the lakes afforded conditions for the rapid deposition of sediment that are seldom excelled. The result was that, in the stream channel over fifteen feet of sediment was deposited. Along the banks the deposition ranged from a very thin layer on the higher portions to ten or even more feet at lower levels. Lieut. Woodruff says in regard to the average rate of deposition : "I think that the average increase of elevation of the immediate banks of the river and principal bayous from near Carolina bluffs to the present head of the raft, during the past thirty years, is about 3 feet. Mr. James Marks, an intelligent and observant resident near Carolina bluffs, estimates this deposit at five feet."t In the lakes the deposition was much more irregular and generally slower. There seems to be no way of determining even approximately the deposition in the lakes. In the region of the Indian mounds in Sec. 5, 19 N., 14 W., which was all under water during the raft period, there is a layer of stiff red clay from 6 inches to a foot thick overlying a black sandy clay similar to that on the Caddo prairie. *27th Cong. 1st Sess. Senate Doc, vol i, No. 64, pp. 3-4. + 43d Cong; 1st Sess. House Ex. Doc. vol. 2 part 2, p. 642, 1873. Ill] Shrkveport Area ; The Raft 171 The deposition near the main bayou mouths was undoubtedly much greater. Parts of the old Cypress bayou channel, in the region of Albany, was filled to the level and above the banks of the old stream by the material brought down by Red bayou. After the cutting of Sewell's canal with the resultant diversion of the waters of Red bayou, a great deal of sediment was deposited in the lower part of Ferry lake. H. C. Collins gives an interesting account, in 1872, of the passage of the water of Stumpy bayou into Ferry lake. He says : " Most of the water follows the bluff, and passes into Ferry lake on its north side, the current running west up the north side of the lake about a mile, and depositing in it a large amount of its mud. At times of rapid rise of the river there is a strong current up the lake to the west, so that sometimes Red river water is .seen beyond the Texas line."* Changes Due to the Removal of the Raft Deepening of the river channel. — After the removal of the raft the current immediately commenced removing the sediment deposited during the raft period. Attention was first drawn forcibly to the erosion of the channel by a peculiar obstruction in the river about 15 miles above Shreveport, known as the " Dawn Stumps." There were several hundred of these standing upright in the bed of the river and when the raft was first removed, boats passed over them without difficulty. In 1886 they pojected six feet above the surface at low water and those in the middle of the channel were cut off as near the water surface as possible. The following year, at the same stage, the stumps, that had been cut, projected four or five feet above the surface of the water.f They were finally entirely removed with high explosives. Maj. J. H. Willard, U. S. E. about 1892, succeeded in recov- ering some of the benches of the Woodruff survey and so determined the exact amount of the erosion since the removal of *lbid, pp. 657-658. f J. H. Willard. Preliminan- Examination of the Lakes connected with Red river, etc. 50th Cong, ist Sess., House Ex. Doc, vol. 4, p. 1490, 1887. Also, An. Rept. Chief of Eng. for 1887, vol. 2, p. 1490, 1887. 172 Geological Survey of Louisiana [Sect. the raft. He says : " Having recovered some of the benches of Maj. Howell's and Lieut. Woodruff's surveys, and reduced the levels to Cairo datum, it is found that the water line has fallen more than 15 feet at the head of the raft, diminishing to about 3 feet, at Shreveport, while a similar reduction has been going on in the river below."* Thus the river is tending to return to the conditions which existed before the raft period. Drainage of the lakes. — In the lake region the irregular deposi- tion of sediment has rendered the return of that region to pre- raft slower than in the main channel. Certain of the old channels have been more than filled with sediment and the streams which have been forced by this filling to flow over older, harder beds have not yet succeeded in cutting channels in them to a depth equal to the depth of the old channels. The reduc- tion in the size of the lakes, though hindered in this way, has nevertheless been very marked. Sodo lake is a very noticeable instance of this reduction in size. (Compare plates 14 and 16.) Poston's lake has returned to very nearly it former condition. This is because the raft had not been above the mouth of Pos- ton's bayou long enough to fill its old channel, and hence this lake experienced none of the difficulties of the lower lakes. At Silver Lakef the former outlet has been entirely filled and the water is engaged in cutting a new channel through the older clays on which it has been forced. Simpson's lake, a lake w^hich formerly existed just above Elmer's bayou, and Dooley's lake, have been almost entirely obliterated. During the raft period they were almost completely filled with sediment and after the removal of the raft the lower- ing of the river channel by erosion completed the drainage. The cutting out of the river channel has resulted also in the partial drainage of the small lakes in the bends on the east side of the river. Marks' lake has shrunk to two small lakes, and the encroachment of the river on Adger's lake threatens to com- pletely destroy it. Dutch John's lake has shrunk to about one- * \x\.. Rept. Chief of Eng. for 1893, pp. T909-1910, 1893. + This Silver Lake which occupied a valley in Coushatta bluffs, should not be confused with the now dry Silver lake near Shreveport, which has entirely drained since the removal of the raft. Ill] Shreveport Area: The Raft 173 third of its former size. Near Shreveport, Swan lake is com- pletely destroyed. Cross bayou discharge. — After the removal of the raft and the formation of the second raft, which forced nearly the whole of the river current to flow through the lakes, the water seeking the shortest channel through the bottoms cut the channel known as ' ' The Pass ' ' between Sodo and Ferry lakes ; and nearly all the water returned to the river through Cross bayou. Before the closing of the outlet ba5^ous, even after the removal of the raft, the discharge of Cross bayou in medium and high stages of water was always greater than either Twelve Mile bayou or Upper Red river. Changes Resulting from a Combination of Causes Reversal of draiyiage systems. — The great discharge through Cross bayou, while the river about Hurricane bluff was clogged with raft material, resulted in an upstream current at times as high as Benoit's bayou*. Fuller states that the upstream cur- rent ran as far as "half the distance between Shreveport and Red bayou, ' ' or as far as Willow chute. Woodruff questions this.f Ivinnard's early account, however, agrees with Fuller. He says : ' 'During the freshets the greater part (of this water) sweeps directly across the channel of the river, and continues eastward to the Bodcau lake ; a portion ascends the channel to Benoit's, or Williams' bayou, or the Willow chute and the remainder passes down the channel J The cutting of Sewell's canal has resulted in the reversal of the drainage for about a mile down the bayou. A new channel was made across the old Henderson fields between 1864 and 1871 and water flowed from Dooley's lake through it and Old Red bayou to Sewell's canal. § A number of the bayous and canals which were outlets during the raft periods have, since the removal of the raft, became inlets. This is true of Alban's canals and Poston's bavou. *Long. 27th Cong., ist Sess., Senate Doc, vol. i. No. 64, pp. 9-10. f 33d Cong., 2d Sess., Senate Ex. Doc, vol. 7, No. 62. { 28th Cong., 2d Sess., Senate Doc, vol. i, No. i, p. 289, 1845. . § An. Rep. Chief of Eng. for 1873, p. 658. 174 Geological vSurvey of Louisiana [Sect. Formation of the delta at the foot of Cross lake. — The peculiar delta at the foot of Cross lake has already been described under Cross lake, and the peculiar fact noticed that, at present, in ordinary stages of water the water flows from the delta instead of into it. Under the old raft regime the great amount of water sweeping through the pass from Sodo lake into Cross lake must have carried with it a great deal of sediment and thus silted up the lower end of Cross lake valley. The ancient stream channel was entirely filled and the present outlet was thus forced to flow over projecting points of the older, harder Eocene material. The delta at the head of Bowman's chute is one of the incidents of the silt- ing up of the foot of Cross lake.* Formation of irregular ridges in the bottoms. — Along the river front and the banks of bayous, where the sandy front land is well developed, the surface is often very irregular as if a great volume of water had rushed through in time of flood, cutting a multitude of little gullys and leaving little irregularly shaped knolls one to two feet high. They are markedly different from the natural mounds of the post-oak or upland flat region ; they are not so uniform in shape, so symmetrical, being irregularly oblong rather than circular, and, a minor difference, they are not so high. The ridges are well developed in Sec. 33, 20 N., 14 W. The theorj' of the current origin of the upland flat topography hardly seems probable when these unquestionably current-formed mounds are seen. Old shore line at Cross lake bridge. — Extending along the base of the hills and about 15 feet above the present water level is a little wave formed bluff ranging from a few feet to 12 feet in height. It represents the old water level of the lake. As the interval between the formation of this lake and the removal of the raft was about 60 years, this bluff represents the effects of 50 years' wave work. It is best developed just east of the south end of the railroad bridge. (Plate 17.) *0n plate 15 a delta is shown only at the head of Bowman's chute. This was the only portion of the foot of the lake carefully examined. The other channels should show the same peculiarity. Ill] Shreveport Area : Geology 175 Geology of the Bottoms. Formations Represented. Recent beds. — The recent Red river deposits cover the greater part of the area and consist of all gradations from a light red sandy loam to a stiff, dark red clay. In places it exists as a mere veneer over the presumably older deposits ; in others it covers it to great depths. Older beds. — Outcropping here and there through the bottoms and exhibited in places along the river banks are beds of blue clay markedly different from the river deposits formed under the present regime. Its altitude varies greatly*, indicating consider- able erosion. The blue clay outcrops in several places at Dooley's bayou, in the bottom of Willow pass and Albany flats. At the last two places, the blue clay seems to be simply a weathered continua- tion of the dark gray Eocene clays of the adjoining bank. On the west bank of the river in the S. W. % of the N. E. % of Sec. 3, 19 N., 14 W., there is a limited exposure of the older clays. On the opposite side of the river only the recent reddish sandy loam was seen ; about 200 yards above the point where the section was taken only the most recent deposition filled with logs of the raft, occurs. The section here exposed is : Section, Red River Bank, James Eric Place {Sec. 3, ig N., 14 IV). 3. Light reddish yellow sandy loam containing numerous specimens of Helix; grading above into surface loam, 10 ft. 2. Dark bluish black, crumbly clay grading below into red sandy clay 6 ft. I. Jointed clay containing numerous irregularly shaped calcareous concretions. Blue above, mottled with red below 7^ ft. The two lower strata seem to be in part represented in the Caddo prairie section, though that section contains more sand. In the southern part of Caddo prairie the older beds are repre- sented by beds of poor yellow and red clayey sand, very different from the sandy front lands of the river but similar to the sands 176 Geological Survey of Louisiana [Sect. of the adjoining hill lands. The upper part of the red sands grades into a very fertile black sandy loam showing in places numerous specimens of UnionidcB. Caddo prairie occupies -the highest part of the back bottom lands. This layer of black sandy loam with Unios appears in the sides of the bayous in several places in the bottoms, commonly over- lying the same poor sands. Age of the beds. — The exact age of these beds can only be a matter of conjecture. The blue clay suggests the Port Hudson beds of Hilgard and the spirited discussion of the age of the blue clay of the Mississippi bottoms. In this region some of the blue clay is clearly part of -the adjoining Eocene formations, as at the rapids at Albany flats and Big Willow pass. The poor red sands may represent outliers of the Eocene hill lands or may belong to the same age as the upland fiat deposits. Examples of unquestionably erosion-formed outliers are to be seen in several places in the bottoms. Just above the mouth of Black Eake bayou are two mounds which are merely detached portions of the hill-lands. Pine island in Clear lake seems to be of the same class. The data at hand are, however, at present a little too meagre to admit of drawing any ver}^ definite con- clusions on the exact age of the sands. Shells from the frojit land. — Some of the light yellowish-red loam which occupies the immediate banks of the river is extremely loess-like in texture and appearance. The resem- blance is greatly strengthened by the presence of numerous land shells. Mr. C. T. Simpson, of the U. S. National Museum, has identified the following species from Sec. 14, 19 N., 14 W. : Pyramidula alterjiata, Polygyra palliata.f Polygyra thyroides. Omphalina friabilis. Polygyra claicsa. Helicina orbiculata. Polygyra inflect a. To this list of species Mr. Simpson has added : " We do not have any of the Oinphalhia friabilis quite so flat as the species you send, and one or two others are a little different from the ordinary manifestations of the same species. P. ilij'roides as sent by you has a closed umbicilicus and in our shells it is open." Ill] Shreveport Area: Soils 177 A comparison of specimens shows the following species from layer three of the James Eric section : Soils* Varieties. — The partially complete soil map accompanying this report shows but three soils, viz. : 1. Red sandy loam. (Front land.) 2. Stiff red clay. (Back land.) 3. Black sandy clay. (Prairie.) These are the principal types, but by the mixing of different proportions of the three kinds an almost indefinite number of varieties are produced. Number one grades into number two, making it quite difficult to say just where one begins and the other ends. The line between the second and third is generally well marked if the land has not been plowed. The red, stiff land thins out to a feather edge on the edge of the prairie land ; when the land is plowed the two are thoroughly mixed, forming a com- plete series of soils from one to the other. f It often happens that a thin veneer of stiff red clay will over- lie a layer of sandy loam. In plowing these are thoroughly mixed, forming what is locally called "dough-faced land." A mixture of back-land and prairie-land produces " black stiff land." Peculiarities and distribtUion. — The red, sandy loam occupies the highest portions of the bottoms along the immediate banks of the river and the old outlet bayous. The predominant tree is *No satisfactory account of the soils can be written until they have been analyzed. Such analyses of the samples collected in this region are now being made under the direction of Dr. Stubbs. Reports of these analyses will be published in Dr. Stubb's work on the soils of the State. The notes here offered are rather on their general aspect and location than on their agricultural value. t On the map an attempt has been made to show only the predominate soil. Thus, if an area is mapped " front land " it does not mean that the land is always typical red, sandy loam, but that the red, sandy loam is the principal constituent of that soil. The overlapping of one material on the others makes satisfactory soil mapping quite difficult. The surface maybe typical stiff red land and an inch or more below, black land. The depth of the lower layer 'varies greatly over even a small area. L 178 Geological Survey of Louisiana Sect.} the Cottonwood ; but ash, hickory, red oak and sweet gum also occur. As the distance from the river and bayous increases the amount of sand in the soil decreases and at a short distance from the stream channels the sandy front land has changed into stiff clay back land. This ranges in color from a dirty cherry-red to a rich dark mahogany. Here the cypress and hackberry find con- genial homes. The surface aspect of the little spots of prairie land scattered through the bottom is markedly different from that of the sur- rounding heavily wooded country. There are a few scattered cottonwoods, numerous scrub thorns (hawthorn and honey-locust) and grass ; altogether a sort of forbidding looking place, but when cleared yielding excellent crops. If the soil is in any way washed off, leaving the underlying red and yellow clayey sand^ the fertility of the field is a thing of the past. Origin. — It is easy to see the manner in which the front and back land have been formed. Indeed it has been so often stated and is so well understood that a very brief statement will suSice here. When the water flows over the banks in time of high water its velocity is greatly checked and it deposits its heavier sandy- material on the immediate banks of the stream ; thus forming; the sandy front land. The waters which now contains only the finest sediment passes into the lower parts of the bottoms, form- ing great temporary lakes. Having little or no velocit3^ the water is unable to keep even this very fine sediment in suspen- sion. This is gradually deposited, forming a stiff clay. In times of high floods the sedimentation is very large. Large areas of stiff back sand are often sanded. Thus, in the flood of 1892 Cottonwood bayou covered a large area of stiff land lying along its banks with sandy material. It is stated that in places this deposit amounted to two or three feet. The formation of the prairie land can only be a matter of con- jecture. The Eocene Tertiary of northern Louisiana abounds in little bare spots caused by the outcropping of unusually calca- reous beds. It may be that certain layers of the older beds in the bottoms contain a large amount of calcareous matter and are responsible for the formation of these spots. The section given above (p. 175) shows quite a calcareous layer. ni] Shreveport Area : Water Supply 179 There is, however, a very widespread black calcareous layer through the bottoms, which contains numerous mussel shells {Unio7iid(e) . It may be after the partial erosion of the valle}', in which island- like outliers of the hill land were left above the surrounding bottoms, that a period of marsh or swamp conditions ensued, in which the water plants formed a peat-like deposit over the sandy clay. A slight deepening of the water and a deposition of sedi- ment on the top of the vegetable matter would make a cozy home for the Unios. Here they lived and died in great numbers. On the re-elevation of the ground and the decomposition of the veg- etable matter the result would be a very black sandy clay with Unios. Water Supply Sources of wafer. — Water can generally be obtained in the front lands at a depth of from 35 to 85 feet. The common method employed is to point a pipe and drive until water is reached. Water obtained from this la3'er is generelly not very wholesome, containing as it does quite an amount of mineral matter. When used in boilers it ' ' scales ' ' badly and on Mr. John Sentell's place "eats out" the boiler tubes. He has succeeded in obtaining partial relief by pumping the water into a tank and exposing it to the atmosphere for from 36 to 48 hours. Mr. A. L. Pullin, a well driller at Shreveport, states that he has succeeded in getting ver}- pure water from a soft red sand- stone at depths ranging from 160 to 300 feet. General sedioji of Red river wells below Shreveport. — Mr. Pullin has kindly furnished the following general section : General Section of Red River Wells below Shreveport. 1. Red soil, sandy loam 4-10 ft. 2. Red clay and sand. Waterbearing. This stratum is claj^ey above and becomes more sandy below. The lower 5-10 feet is a quicksand. This layer is the source of the highly mineral water which is obtained in the driven wells 45-60 ft. 3. Gravel and sand. Quite firmly bedded, so much so that it is impossible to drive a well into it. i8o Geological Survey of Louisiana [Sect. The gravel sometimes reaches the size of a goose &gg. White chert and quartz pebbles are com- mon. The gravel is largest at the top and gradually grows finer until at the base of the strata it grades into a fine white sand 20-40 ft. 4. Soft grsiy sandy clay containing vegetable remains and occasional shells 8-16 ft. 5. Fine white sand 0-40 ft. 6. Hard tenaceous blue cla)^ called " rubber clay " containing scattered iron concretions about the size of a pea 40-132 ft. 7. Indurate red sand, water bearing. Furnishes an abundance of soft water. Water from this stratum generally rises to with- in ten feet of the surface. None of these deep wells were personally examined nor was I able to obtain any shells from layer 4. It can hardlj^ be doubted, from the general character of the material, that the water is from the older Tertiary strata. The presence of large gravel beds in the river valley is also to be specially noticed for no gravels of northern origin have yet been found on the hills west of the Black bayou and Baj^ou Dauchite gravel trains. WeH at Lotus Landing, Robson P. O. — At the time of the writer's visit Mr. Pullin had just finished a well on the place of Capt. Robson at Lotus Landing, in 16 N., 12 W. from which he had a large suite of gravel specimens. Well Section on Capt. Robsoti's Plantation {16 N. 12 W.). Thickness Red sandy loam 4 ft. o in. Fine red clay with sand 75 ft. o in. Red sand, water bearing 3 ft. o in. Gravel and sand, same as 3 in fore- going section 24 ft. o in. Organic clay with shells 12 ft. o in. Brown lignite 3 ft. o in. Good black lignite 2 ft. o in. "Soapstone," soft white friable clay. 7 ft. o in. \''erv hard blue limestone o ft. 8 in. No. Depth I. 0- 4 2. 4- 79 3- 79- 82 4- 82-106 5- io5-ii8 6. I 18-121 7- 121-123 8. 123-130 9- 130-131 Ill] Shreveport Area : Physiography i8i 10. 131-135 Hard black lignite 4 ft. 3 in. 1 1 . 135-225 Blue clay 90 ft. o in. 12. 225- Water in sand, not passed through. Any separation of this section in beds of different ages must be necessarily a mere guess. It will be quite necessary to have good samples from each of the different layers in order to arrive at even a partially satisfactory conclusion. The section is, however, quite suggestive. Layers 2 and 3 may represent the Port Hudson of Hilgard. Layer 4 suggests the Lafayette or Orange sand, whatever that name may really mean, and the lowest part seems to be older Kocene Tertiary. Physiography of the Bottoms Waterfali^s and Rapids Descriptio7i. — It is a decidedly interesting thing to find in the midst of an old, well developed, river flood-plain, waterfalls and rapids. Several were seen in upper Caddo bottoms and there are doubtless others in localities which have not been examined. The most perfect waterfall seen was at the outlet of Silver lake just below Coushatta bluffs. The waterfall is about ten feet high and is at the head of a little gorge probably 300 yards from the river. The crest of the waterfall is composed of hard bluish-gray and red sandy clays. Collins describes a waterfall formed by the water flowing over a hard clay layer underlaid by sand, in a channel accross the old Hamilton fields from Dooley's bayou to Old Red bayou.* There are also rapids in the main Dooley's bayou channel, about a mile above its entrance to Old Red bayou where the water flows over a layer of hard clay. This is sometimes called " Dooley's Falls." We have before spoken of the rapid current at Big Willow pass and the rapids and small waterfall at Albany flats. These are, of course, not noticeable in very high water when the inequality is not enough to effect the large volume of water greatly but in moderate stages they are very marked. *43d Cong. 1st Sess., House Ex. Doc, vol. 2, part 2, p. 658. 1 82 Geological Survey of Louisiana [Sect. There are very marked rapids in Bowman's chute, just above where it joins Middle bayou and the "Ditch" forming Cross bayou. Formatioyi of waterfalls and rapids. — During the raft period many of the old stream channels were covered by lakes. The sediment deposited in these lakes often more than filled parts of the old channels so that after the removal of the raft and the partial drainage of the lakes the streams were forced to cut new channels. It would sometimes happen that a stream thus forced out of its channel would find itself superimposed on the older blue clays or on projecting points of the adjoining Eocene clays. Such a stream may, in its course, find its way back into a portion of the old stream bed which has not been filled. The fall thus developed on the bank of the former stream will wear rapidly back through the alluvium till the face of the blue clay is reached. At this point, if there is a layer of harder clay under- laid by softer material, the waterfall will maintain itself and gradually wear back until the lake formed by the daming of the old stream channel is reached. If the clay is a uniform mass the face of the falls will be worn off and rapids produced. In this region the same result could be produced without the formation of a waterfall by the tumbling of the stream over the old stream bank. If the old channel has been completely filled the water will flow in the lowest part of the adjacent land ; part of its bed being of alluvial material and part possibly of the older clays. As the river erodes its channel the side streams would tend to do likewise and would soon cut ample channels through the alluvium lying between the older clays and the river, leaving the less easily eroded clays to form rapids and waterfalls in the channel. In the case of the rapids at Albany flats the ancient channel was evidently to the north of the present channel. This old channel was filled with sediment brought down by the outlet bayous. When the raft was removed the stream occupied the lowest land, which, since the greater part of the filling was on the northern side of vSodo lake, was along the base of the hills. Here the stream found hard blue Eocene clays. The rapid erosion of the alluvial material between these clays and the river left them ni] Shrbveport Area: Lakes 183 to form rapids in the channel. The rapids are gradually wear- ing backward and the day is not far distant when Caddo parish will be the richer by a number of acres of good land where there is now a lake. It is believed that the ancient channel at Big Willow pass is also to the north and that the blue clay will finally, after the Albany rapids have worn out and drained Sodo lake, wear back and drain Ferry lake. The rapids on Bowman's chute are of exactly the same type, were formed in the same way and will have same life history. The falls at Dooley's bayou are slightly different from those just described. It seems that as the raft advanced up the river the little ditch which drained the old Dooley's swamp offered a good outlet channel ; water rushed through it and tumbled over the bank of Old Red bayou. The falls thus formed wore back until the blue clay was reached when a rapids was produced. A portion of the water turned over the old Hamilton fields and fell into Old Red bayou. Here there was a layer of hard clay underlaid by softer clay, the exact conditions for a typical water- fall, and as the under sand washed out portions of the clay strata broke off, thus maintaining a perpendicular fall. At Silver lake the old channel was to the south of the present outlet. The filling of this resulted in the tumbling of the water over the bank at a place occupied by a projecting point of the Eocene clays. A waterfall resulted whose height has been increased by the deepening of the main channel of the river. The fall is wearing back by the removal of the lower layers by the water and the caving off of the upper strata and will soon reach and destroy Silver lake. Origin of Bottom I^akes Classes. — With reference to origin, there seems to be three types of lakes in the bottoms, viz. : 1. Cut-off lakes. 2. Lakes of enclosure. 3. Raft lakes. , Cut-off or Horseshoe lakes. — Lakes of this type are not well developed in this part of the valley, not nearly so well as they 184 Geological Survey of Louisiana [Sect- are in the lower Red river valley. The most perfect example is Moon lake or Old River lake, east of Oven bayou, on the line between 19 N. and 20 N. A river in an alluvial flood plain is constantly cutting the banks on the outside and filling on the inside of the bends. When two parts of a great bend approach near each other the intervening neck will be cut through in a freshet, forming a cut-off. The connections between the river and the portions of the river cut-off will gradually become filled with sand-bars and in time entirely separated from the river. As the river travels across the valley the lake thus formed may be left several miles from the river. Several such cut-offs have been formed in this region, with a little help from man, in the last fifty years. Near Hurricane bluffs is the Shreve cut-off of 1837. Benjamin's cut-off near Willow chute, and the Hotchkiss cut-off above Shreveport, have been formed in this way. Lakes of iyiclosiire. — The second type of lakes is quite com- mon. They owe their origin to the formation of natural levees by the river. Along the east bank of the river this is well exemplified, where the river strikes the hills and then makes three great loops far out into the bottoms. In these loops, mini- ature bottom basins are formed ; the hills forming one side and the elevated land along the banks of the river the others. In these basins water collects forming little lakes. To this type belong Adger's lake, Marks' lake, Dutch John's lake and a little lake on Black Lake bayou in Sec. 12 and 13, 22 N., 15 W. A similar little lake may be formed entirely by the river with- out the aid of the bounding hills. In a great ox-bow bend where there is in one place only a very narrow neck of land between two parts of the river the elevated land which forms the banks of the river will extend entirely across the neck, forming in the interior of the bend a complete basin. Water accumulates in these depressions forming lakes. On plate 14^ lakes of this type are shown in the center of the bend at Hurri- cane bluffs and in the old bend at the Willow chute outlet. A similar lake of inclosure is found near Blake Lake bayou in Sec. 14, 22 N., 15 W. There is still another way in which a lake may be formed by inclosure. Not only has the river built its banks up higher Ill] Shreveport Area: Lakes 185 than the surrounding land but each little bayou has done like- wise. Thus a basin is formed in the inter-bayou space. The old Dooley bayou swamp and the now filled Simpson's lake probably occupied such depressions. Old Swan lake just above Shreveport, between Twelve Mile bayou and the river was of this type. Raft lakes. — The origin of lakes of this type has already been discussed under the headings ' ' Growth of the Raft ' ' and " Changes due to the Formation of the Raft " and Ferry, Sodo and Cross lakes were referred to this type. It remains, how- ever, to call attention to the similarity in position and origin of these lakes to the other large lakes of Red River valley ; to give the traditions and historical data we possess regarding them and to give some other theories which have been advanced to account for them. A reference to a good map of the State of Louisiana will show lakes which are the exact counterpart of Cross lake and Sodo lake all along the river valley below the Arkansas line. Those which have been clearly formed by the drowning of old stream valleys and which belong to the same type as Cross and Ferry lakes are : Lake Bodcau, Wallace lake, Lake Bistineau, Black lake, Saline lake, Spanish lake, Lake Terre Noir, Lake Nan- taches and Lake latt. There are also several which have been formed in bottom basins like Sodo lake. The two most pro- nounced of these are. Lake Cannisnia and the lower part of Bayou Pierre lake. They are so alike in their general features and occupy such analogous positions that any theory accounting for the origin of one must, in general, cover the origin of all. Of the recent origin of the lakes in the upper part of the val- ley there can be little question. A number of planters of Red river bottoms have repeated to me the old Caddo Indian tradition that about one hundred and fifty years ago the land now occu- pied by Sodo lake was an oak ridge, that all the water flowed in a narrow cypress-fringed bayou in the center and that the filling of the valley was sudden, as if by an earthquake. Collins evidently heard much the same story, which he states in this way : " Mr. Josey, living at Swanson's landing, who is probably the most intelligent man in the vicinity, thinks there 1 86 Geological Survey of Louisiana [Sect. was a general subsidence of a very large tract, including the bluffs as well as the bottoms, and that it took place since the removal of the Caddo Indians. He says, that a few years ago, when a few of the Caddo Indians came back to visit the country they told him that they used to cultivate cornfields on land adjoining these oak and pine stumps, and now covered with water to the same depth, and that the entire country was above overflow."* The statement of the Indians is in part substanti- ated by a group of mounds in Sec. 5, 19 N., 14 W. A compari- son of the two maps accompanying this report will show that the site of these mounds was covered by Sodo lake during the raft period. Dr. Joseph Paxton, in a letter written in 1828, gives a similar account of Bodcau lake. He says: " Bodcaw prairie is repre- sented to have been exceedingly beautiful, and thirty years since was the resort of immense herds of buffaloes. It is now a stag- nant lake."t These statements, together with very positive evidence furnished by the only partially decayed trees in Ferry lake shows a very sudden and recent origin of these lakes. The most common theory of the origin of these lakes is that they were formed by the sudden lowering of a portion of land by earthquakes ; in a similar way and at the same time as the Sunk lands of the St. Francis basin and Reelfoot lake near New Madrid, Mo., which were formed by the earthquake of 1811-12. Lyell, in his Principles of Geology, nth edition, vol. i, page 452, after quoting Darby's statement that the lakes have been formed by the damming of the mouths of the tributary stream valleys with the Red river alluvium, suggests that they owe their origin in part to earthquake action. Lyell had just visited the sunk region about New Madrid, and was greatly impressed with the phenomena there shown. There are several reasons for believing that the lakes do not owe their origin to earthquakes. Probably the most satisfactory are the results obtained in the borings made by the Cypress bayou survey in 1892 under the direction of Capt. Willard. Of *43d Cong. 1st Sess. House Ex. Doc, vol. 2, part 2, pp. 658-659, 1873 J An. Rept. Chief Eng. for 1873, pp. 658-659. t 20th Cong. 2d Sess. Senate Doc, vol. i. No. 78. p. 10, 1829. Ill] Shreveport Area : Lakes 187 the results of these borings Capt. Willard says : " The borings also disprove the notion that these lakes were formed by the same convulsion that made those at New Madrid, the strata plainly being water deposits without contortions that the upheaval or sinking would produce, and the oak stumps as well as the cypress are everywhere found vertical."* The second reason is that a theory of origin similar to the New Madrid lakes will hardly account for the peculiar positions of these lakes. Lakes of the type of Sodo lake and lake Cannisnia might be produced by the sinking of an area of land in the bottoms by earthquake action, but it must be confessed that it would be a most peculiar earthquake or series of earthquakes which would drop the bot- tom out of every large valley entering Red river valley, or which would raise the land at just the points where these valleys enter the river valley. This drives us to the supposition that the sub- sidence was not local but extended over the whole valley ; effecting the hills and bottoms alike . Such a movement is different from the local subsidences in the bottoms produced by the earth- quake at New Madrid. A general movement of this kind over a large area is more likely to be produced by slow crustal move- ments than by an earthquake. A general subsidence of this kind is capable of producing such lakes. As the subsidences progresses, the river wdll commence building up its channel and banks in an effort to regain its base- level. If this movement is rapid. Red river with it great amount of sediment will build up its bed much faster than the less muddy tributaries. This will result in the elevation of the river above the tributary streams and the consequent ponding of the water in their valle^^s. The fact that there is abundant evidence that the southern part of the United States is sinking f seems to corroborate this theory, but other facts, at hand, do not sustain it. If such a * An. Rep. Chief of Eng. for 1893, p. 2069, 1893. t This evidence consists in the estuary character of the mouths of the majority of Gulf rivers ; the great depths of some of the costal rivers ; the observations of Maj. J. B. Quinn of the U. S. Engineers, and the buried shell heaps on the coast. See Five Island article and Geol, Surv. of Ala,, 1894, pp. 45-47- 1 88 Geological Survey of Louisiana [Sect. subsidence is going on it does not seem probable that the line of maximum depression should follow the Red river valley, and if it extends over a large area all the streams of that area should be affected alike. That is, we would look for lakes of the same type along the valleys of the Brazos, the Trinity, the Sabine and the Ouachita and especially along the Arkansas, which in point of size and amount of sediment it carries, fully equals the Red. Lakes should also be found in Red river valley above the region effected by the raft. No lakes like Ferry, Cross or Bistineau lakes are found. This seems to leave only the theory of the raft formation of these lakes. This theory is greatly strengthened by the known formation of a large lake similar to Sodo lake just below Miller's bluffs by the closing of the outlet bayou by the raft. Then there is the simi-historical account of the formation of Sodo lake proven as it is by the old tree stumps and the Indian mounds. This theor>^, however, requires that the lakes be drained on the removal of the raft. This has not been fully accomplished, although a large part of the lake area has been drained. There are several possible reasons why the drainage has not been com- pleted at the present time : (i) the river may not as yet have succeeded in cutting out all the material deposited in the channel during the raft period, (2) many of the streams have been super- imposed on older clays by the filling of their old channels and have not yet had time to cut new channels to as low a level as the old channels. If, as now seems probable, the lakes owe their formation to the raft, it is possible to approximate the date of the forma- tion of Cross and Ferry lakes. The distance, counting the old stream detours, from Cross lake outlet to the head of the Shreve raft in 1838, is 49 miles. If four-fifths of a mile represents the normal rate of advance of the raft, about 61 years had elapsed in 1838, since the closing of Cross lake bayou by the raft. This would make the date of the formation of these lakes about 1777. Ill] Shreveport Area: Uplands 189 Notes on the Geology of the Hill-lands * The Upland Flats + General characters. — The point of land between Ferry lake, Clear lake, James ba^^ou and the dotted line on plate 16 shows a marked topographical difference from the land north of it and from the land on the south side of Ferr}^ lake. The country in the last two mentioned localities is hilly and has fairh' mature stream valleys. The area under discussion, although from 30 to 40 feet above the adjacent drainage systems, has no well developed stream valleys. The water finding no outlet forms little swamps between the little mounds or hillocks with which the country is covered. These mounds are nearh^ circular and range from 20 to 80 feet in diameter and are from 2 to 6 feet in height. The composition of these mounds is quite different from that of the intermound spaces, being a moderately fertile sandy loam, while that between them is a poor stiff gray or yellowish gray clay, commonly called ' ' post-oak clay. ' ' The intermound spaces are filled with water , forming little puddles and supporting a growth of swamp or pin-oak and post-oak. The mounds are covered with post-oak and short leaved pine. Under the ' ' post-oak clay' ' at depths var>4ng from a few inches to several feet, is a hard red clay. This is exposed o\Ay in the occasional gullies. The distribution of these upland flats is quite extensive in this part of Louisiana. The}^ are well developed just north of Wal- lace lake. In Bossier parish they occupy a strip of land between Carolina bluffs and Bodcau lake and east of bayou Bodcau they extend almost to Fillmore. The great level land between bayou Bodcau and bayou Dauchite in northern Webster, may belong to the same class. There seems to be a great piece of very flat uplands, j'^ounger than the Eocene, lying between bayou Bodcau and Red river in northern Louisiana and southern Arkansas. In this upland flat there are two island-like masses of Lower * As the main part of the work was in the bottoms, only occasional oppor- tunities presented themselves for examining the hill-lands. fLerch, Bull. La. State Exp. Stations, Geology and Agr., Part 2, 1893, p. 106. iQo Geological Survey of Louisiana [Sect. Claiborne Eocene ; one occupies an area south of lake Bodcau and includes Bellevue, Fillmore and Haughton ; the other is rep- resented by the red lands of the northern Bossier. Well sectio7is. — Only very shallow wells have been sunk in the upland flats and of these we have only very incomplete records. They, however, agree in finding occasional fresh water mussels {Unionida). The well diggers are quite positive that they were exactly like the shells now living in the adjoining lakes. A well in the S. W. )i of the N. E. ]i of Sec. i, 20 N., 16 W., gave the following section : Well Section S. W. %ofN.E.%, Sec. /, 20 N., 16 W. 1 . 0-4 Fine loamy sand 4 ft. 2. 4-1 1 Yellow and gray mottled clay, post-oak clay. . . 7 ft. 3. 1 1-29 Red clay with calcareous concretions in lower part 18 ft. 4. 29-46 Blue mud with vegetable matter and mussel shells 1 7 ft. 5. 46-55 Fine blue sand, not passed through 9 ft. A well digger living just north of Wallace lake reported that in a strip of country about two miles wide, just north of the lake, he had found ' ' mussel shells ' ' at depths from 1 8 to 30 feet in all but two wells. Shells were very abundant in a well on the Pat- terson place in the N. E. ]i of N. W. }i Sec. 34, 16 N., 13 W. The well was sunk on an outlying hill 45 feet above the level of of Wallace lake. The shells were found at a depth of 20 feet. In a well sunk on the I,ittle place a great many shells were found between 25 and 30 feet. The old dump heap at the Patterson place was examined and a few fragments of Lhiios found. As it was possible for these to have been scattered there since the dig- ging of the well they can not be considered conclusive. Colored sands a7id clays. — Where large sections of these beds are to be seen along the water courses very heavy beds of bril- liantly colored sands and clays with calcareous concretions are to be seen. This is especially noticeable near Red Chute bridge in Bossier parish. On the road, which is about 50 feet above the bottoms, from Bellevue to the bridge, about three miles from the bridge deep red clay filled with lime concretions outcrop in the Ill] Shreveport Area : Uplands 191 hillsides. This cla}^ is markedly different from the red clays of the Tertiar}^ to the east. The concretions are in themselves very distinctive ; these light red, smooth, rounded claystone masses are entirely distinct from the red ironstone concretions of the old Tertiary. For about a half a mile east of the bridge the clay is overlaid by thick beds of red silty sand. Red Chute hill, where the road descends from the uplands to the bottoms is about 50 feet high and the washed road cut shows good exposures. It is composed entirely of fine grained red sand and loam with a little red clay. An exposure of these sands was seen at Carolina and Hurricane bluffs. Carolina bluffs are composed of about 60 feet of light red with some white and yellow, cross bedded-sands. Lenticular masses ot red clay are scattered through the sands. In the upper portion of the hill a thick bed of red clay is overlaid, for a short distance, by a bed of gray clay two feet thick. The red concretionary clay outcrops in numerous places along the north side of Ferry lake, where the waves have washed out the concretions and formed numerous little pebble beaches. It is also well developed along the north shore of Cross lake, while the southern shore shows the entirely different old Tertiarj^ strata. The first cut north of the trestle over Lake Wallace exposes irregularly bedded white and red sands and red concretionary clays. Weathered surfaces show a red glaze over the whole mass, even over the white sands. Little or no clay was seen in the part of the cut immediately adjacent to the lake, here light colored stratified sands, not effected by dilute hydrochloric acid, are covered by massive brick red sand about four feet thick. Toward the northern end of the cut the calcareous clays and fine sands with very large calcareous concretions become very prominent. The first cut south of the trestle (on the other side of the lake) consists of finely laminated gray clay with sand partings, overlaid by gra^dsh yellow sands which contain lense-shaped masses of clay which have evidently been derived from the under- lying clays. This sand contains numerous specimens of silici- fied wood. Age of the upland Jlais. — The facts at hand indicate that these 192 Geological Survey of Louisiana [Sect. beds should be separated from the adjacent older Tertiary- beds. We have a fresh water deposit resembling more nearly the recent Red river deposit than anything else in the region, but evidently formed under different conditions and occupying a level from 20 to 50 feet above the present bottoms. So far as the stratigraphy of the State is known these beds seem to be most nearly represented by the Port Hudson deposits. This conclusion is greatly strengthened by the observations of Hopkins in lower Red river valley. He says: "On Dunbar's creek the equivalents of this clay (the Port Hudson) form the terraces upon Red river, if the calcareous nodules are a sure guide. These beds partake of the ferruginous aspect of this whole region, and are so intense red that it was not until they were traced laterally into the Mississippi deposits that they were recog- nized as belonging to this group. Examples are seen on the road from Avoyelles to Pineville, at the falls above Alexandria, on the west bank of Cane river in Natchitoches parish, and at Grapp's bluff, above Campte.* Origin of the mounds. — The mounds, which have been noticed as covering the Upland Flats are by no means confined to them. They cover large portions of the Tertiary and Quaternary deposits of Arkansas, Louisiana and Texas. In Louisiana they are very markedly developed in the region under discussion, around Lake Charles and in the Moorhouse hills. They are not confined to any deposit or to any hypsometric level. Entirely absent in one locality they are quite abundant in another. The popular interest in the origin of these mounds is very great and theories of their origin are common. An old darkey offered the following explanation: when the "Great Massa " made this earth he made it with a sieve and when he finished the sifting there were a number of lumps left in the sieve. These were thrown out forming the mounds. Another explanation, of a similar kind, is reported to have been given by the Caddo Indians. Their legend ran that many, many_ years ago the country was inhabited by a race of giants. For some reason, which the legend did not state, the giants were carrying dirt in '■•Third Annual Report Louisiana Geol. Surv. An. Rept. Supt. La. State University for 1871, 1S72, p. 187. Ill] Shreveport Area : Uplands 193 their aprons ; when the dinner horn sounded they dropped the dirt where they stood and hurried away to a dinner from which they never returned. Some of the theories which have been advanced by more cul- tured people are but a step removed from these. Others show considerable thought. The following theories have been advanced bj^ scientists : 1. Ant-hill theory. 2. Wind theory. 3. Water volcano theory. 4. Pressure theory. 5. Gas theory. 6. Indian garden-mound theory. 7. Current theory. 8. Slow erosion theory. The ant-hill theory was suggested by Hilgard in his Supple- mentary and Final Report of a Geological Reconnaissance of the State of Louisiana p. 11; it holds that the mounds were made by a large species of ant, which for some reason was entirely destroyed after the formation of the mounds. This theory seems to greatly tax the ants' abilities. A similar theory sometimes heard among the people of the country, is that the mounds were made by some burrowing animal. Clendenin suggests * that the wind theory was suggested by emigrants from the prairie regions of the northwest, who had seen little mounds of sand or dust form behind little obstructions during a wind storm. Thomassy conceived the idea that these mounds were formed by springs or "aqueous volcanoes." f So far as we know, the pressure theory, which was advanced ;j: to account for mud lumps, has not been directlj^ applied to the similar phenomena, the mounds. It holds that over a semifluid layer of quicksand there has been deposited a thick layer of tenaceous clay. The weight of the upper clay in places bulges * Bull. La. State Expt. Stations : Geol. and Agr. part III, p. 180. f Geologic Pratique de la Louisiane, Chap. VIII, New Orleans, i860. :}: Lyell. Principles of Geology, loth ed.. 1868, vol. i, p. 449, Hilgard. A. J. S. 3d series, vol. i, 1871, p. 425. 194 Geological Survey of Louisiana [Sect. the surface of the ground and forces out some of the underlying mud. The objection to this theory lies in the great range of these mounds in altitude and over beds of different ages. Scattered through all the beds of Louisiana, from the lowest Teriiary to the most recent, there are large amounts of vegetable matter mixed with beds of sands and clays. The decomposition of this vegetable matter forms gas and if this gas in its passage to the surface passes through a bed of sand it will probably carry to the surface some of the sand and so form a little mound. Such cones are now forming near the sulphur well at Lake Charles and formation of the mudlumps seems to be very analogous. This theory was first originated for the mud-lumps by Siddell * and and applied to the mounds by Hopkins. f Clendenin supple- ments this explanation with a hypothetical formation of the gas vents by earthquakes. The theory of the gas origin of the mounds seems to be more nearly supported by the observed facts than any other theory yet advanced. But the exact relation between the water and the gas, which issue from the mounds now forming, has never been fully worked out. It may be that the gas merely accompanies the water instead of the water accompanying the gas. The Indian garden-mound theory is probably one of the most hypothetical yet adv^anced. Nadaillac in his Prehistoric America, p. 182, says: "Between Red river and the Wichita they (the Indian garden-beds) can be counted by thousands. According to Forshey, who described them to the New Orleans Academy of Sciences, these embankments cannot have served as the founda- tions for homes of men. He remarks that none of the known burrowing animals execute such works, whilst hurricanes could not have accumulated materials with such regularity. He added that in his opinion it was impossible to say anything definite with regard to their origin, which seemed to be inexplicable. Other archaeologists are more positive ; they consider that these * Report to Capt. Talcott, 1839, in Humphrey's and Abbott's Report, Appendix A. t First Annual Report of the La. State GeoL Survey in An. Rept. Board of Supervisors of the La. State Seminary for Learning and Military Acad- emy for 1869, p. 82, 1870. in] Shrbveport Area : Mounds 195 embankments were used for nothing but cultivation, and that they are intended to counteract the humidity of the soil, still the greatest obstacle with which the tillers of the soil of the plains of the Mississippi valley have to contend. The last two theories account for the origin of the mounds by erosion ; the first by a rapid rush of waters ; the second by differ- ential erosion.* Neither seems to be at all sustained bj^ the facts. The Oi^der Tertiary Previous work. — A number of geologists have done work on parts of the older Tertiary which border the bottom lands dis- cussed in this paper. By far the most careful and detailed observations on the bordering hills were made by Mr. H. C. Collins, one of Lieut. Woodruff's assistants on the Red River Raft Survey of 1871-1872.! Although not a professional geologist or a man who had had much geological training, his observations have great value as being a concise statement of what he saw. This report was not known to the writer while he was in the field so no investigation was made of Collins' reported find of the Cretaceous fossil, ''Nautilus dekayi and another fossil ' ' in the bluff at the Cypress brake between Henderson's Mills and Albany, and at Irving's bluff. Prof. Harris has suggested that he has in all probability mistaken Nautilus dekayi Mori., iox Enclimatoceras ulrichi V^hiie, and that the beds are probably Midway Eocene. Besides Collins, Hopkins,;); Johnson, § Lerch | and Clendenin^ * Brief statements of this latter theory are given by David Dale Owen, Second Report of a Geol. Reconnaissance of part of the State of Arkansas, Phila., i860, p. 144, and Otto Lerch, Bull. La. State Expt. Sta.,Geol. and Agri., part II, 1893, p. 106. f Geologic Notes of Assistant H. C. Collins. An. Rept. , Chief of Eng., for 1873, vol. I, pp. 651-664, 1873 ; also 43d Cong., ist Sess., vol. 2, part 2, pp. 651-664, 1873. I Second An. Rept. of the Geol. Snrv. of L,a. by F. V. Hopkins, 1871, pp. 9, 22. Also First Annual Report of the Geol. Survey of La., by F. V Hopkins, pp. 86, 89, 1870. § The Iron Regions of Northern Louisiana and Eastern Texas by L. C„ Johnston. 5cth Cong., ist Sess., House Ex. Doc, No. 195, vol. 26, pp. 17— 19, 22, 34-37, 1888. I A Preliminary Report Upon the Hills of Louisiana, North of the Vicksburg, Shreveport and Pacific Railroad, by Otto Lerch. Bull. La. State Ex. Sta.; Geol. and Agr., part i, 1892, pp. 18-19. Tf W. W. Clendenin spent two seasons working on the Geology of Caddo parish but published no report. 196 Geological Survey of Louisiana [Sect. have touched this region but, with the exception of the latter, the work was of an extremely hasty reconnaissance character and our knowledge of the country is very meagre. Vaughan has republished Johnson's Slaughter Pen Bluff section but does not seem to have visited the locality.* It is with a hope of adding something to this meagre information that the facts on the old Tertiary which the writer was incidentally able to collect, while working on the bottoms, are published. What is needed is a very careful examination of the northern Caddo hill-lands ; it has been a guessing ground for quite a number of years. Slaughter Pen bluff section. — This section, which is on Cross bayou just above the water-works, has been examined by both Johnson and L,erch and as has been stated above, Johnson's section has been republished by Vaughan. Johnson considered it a part of Hilgard's Mansfield series, the major part of which is now known to be Lignitie Eocene ; Lerch referred it to his lower lyignitic, which is in part equivalent to the Lignitic and in part to the IvOwer Claiborne. Vaughan suggests that it is probably Lignitic. The discovery of a small A/act?-a in the upper part of the bluff and the general resemblance of this species and the litho- logical character of the material to Buhrstone outcrops in Alabama on the Alabama river has led Prof. Harris to suspect that it may be eventually classed as Lower Claiborne. The section here exposed is : Section at Slaughter Pen Bluff, Shreveport. (Plate 18.) 9. Yellow claj' with plates of calcareous matter grading above into red soil 6 ft. 8. Graj' calcareous concretions 2 ft. 7. Grayish and yellow sandy clay with leaves and shells. . 5 ft. 6. Fine lamellae of brown clay and yellowish gray sand with reddish iron nodules 5 ft. 5. Same as No 6 but without iron nodules. Contains large log of silicified wood 6 ft. 4. Dark drab clay 2 ft. * Am. Geol., vol. 15, 1895, p. 205; also Bull. U. S. Geol. Surv., No. 142, 1896. Ill] Shreveport Area : Tertiary 197 i-^^X iS-5 ■■'■' t:i '^ S-og * s > S rt ^ — O lU "3 ^ XC:^ -5 ^ ^■ :^_ . ^ o ^ ^ >^ 1- S ffl 3. Lignite 2 ft. 2. Gray and yellow sand with fine blue clay layers. Leaves.. 3 ft. I . Gray and yellow, more and less laminated sand with thin la- mellae of blue clay to water level 13 ft. In a gully about one-fourth of a mile south of the Slaughter Pen bluff twenty feet of gray or bluish gray laminated clays overlaid by 15 feet of stratified yellow clays are exposed. The gray clays, like the yellow clays at the top of the Slaughter Pen bluff section, contain thin plates of calcareous matter. The lower clays show several streaks of dark lignitic clay two to eight inches thick. This seems to represent the upper part of Johnson's section. About two hundred yards south of the section shown in the photograph there is a small but extremely distinct fault in the lignite layer. It is probably due to local earth shocks. The fault shows one rather peculiar feature, the down- ward displacement of a portion of the lower lignite along the fault line. Normally this should turn up instead of down. Its present shape could be produced by a double movement along the fault line, that is a movement down- ward and then a movement upward. If the fault at its formation gaped open slightly the layers in the overhanging portion would gradually settle down producing the appearance shown in the figure. 1 98 Geological Survey of Louisiana [Sect. Kansas City, Pittsburg ajid GjiI/ Railroad cut south of Cross Lake bridge. — The large cut on the Kansas City, Pittsburg and Gulf Railroad about midway between the Cross lake bridge and the railroad shops shows a very peculiar collection of great rolled clay boulders in a gray and brown sand. Near the northern end of the cut are about eight feet of interstratified orange, yellow, gray and brown sands and chocolate colored clays. The clay strata are quite thin not over two inches thick in any case (layer A, fig. 5). The layer just above this, B, is a very black lignitic clay. As this approaches the fault line it becomes lighter and grades into a brown sand. This fault only extends half way to the surface. The dis- turbance along the fault line increases toward the bottom where the layers are much crumpled and broken up. Laj^er D is made up entirely of grayish yellow sand with thin pastings of blue clay. In this are the large concretionary masses of calcareous sandstone which are so well developed in the first cut to the south and indeed in all the region about Shreveport. The southern end of the cut is composed of blue clay boulders scattered through a gray and brown sand. These masses of blue clay are rounded and the stratification lines lie in every direction. Some are of large size several measuring 25 by 15 inches. The outer portions of this clay show a rim of yellow clay an inch thick, which has been produced by oxida- tion. Many of the clay pebbles have coats of iron oxide. Through the mass are often beds of sand, one very noticeable one, G, extends diagonally from the top to the bottom of the cut. Through it are scattered very small clay pebbles. These blue clay gravels are shown also in some of the cuts between this cut and the lake. They are also exposed in the road side a little east of Jewella. It is diffcult to conceive the exact conditions under which these large clay bowlder were fashioned out and transported to this place. Vaughan describes an almost identical exposure contain- ing large clay bowlders at Port Caddo, Texas, and concludes that it represents a local unconformity of Eocene age.* If the beds at Slaughter Pen bluff are of Lower Claiborne age the uncon- * Am. Geol., vol. 16, 1895, pp. 304-308. Ill] Shrveport Area : Tertiary 199 formity was formed in the early part of the l,ower Claiborue stage. This conclusion is strengthened by a greatly disarranged exposure seen in a railroad cut about four miles south of Many. Here the disturbed material, which contains lyOwer Claiborne fossils, lies between undisturbed fossiliferous Lower Clairborne beds and fossiliferous lyignitic beds. Sa?ids. — There are few facts bearing on the age of the upper yellow and red sands about Shreveport and in the absence of the same there seems to be no reason for considering them separate from the lower Tertiary beds. The sand beds ai'e well developed on the Spring tract east of the City park. In the street car cut they are seen underlying horizontally stratified gray clays con- taining good leaf impressions. Very similar sands are exposed in the Union depot cuts under lignite and gray clay. These sands contain numerous pieces of silicified wood. No gravel of northern origin was seen in any place over the hills. The ice factory well. — The following letter has been received from Mr. F. J. Lukins of the American Well Works who had charge of the drilling of the deep ice factory well : "I had charge of the deep well that was sunk at Shreveport, but it has been so long ago that we have no record here now as to the different for- mations. You can perhaps get from local well drillers, the nature of the formation to 450 feet. At that depth we passed through a sand rock formation. It was very fine and not very hard, and contained considerable water. We made a well at the Shreveport Junction in this formation, and got a good supply from that stratum. The sandstone formation was about 50 feet thick. From there to 971 feet, it was a sort of blue clay for- mation with occasional very hard streaks of thin shelly rock. This rock itself was very thin, perhaps one-half to one inch in thickness, but there would be several layers together, which would make up a thickness of from 6 to 12 in. At one point, I think about 600 feet, we passed through a stratum of pyrites of iron, which was about 14 in. in thickness. We could not tell whether this formation was solid, or whether it was a collection of small pieces packed together. However, I procured one specimen which was spherical in shape, and about one-half inch in diameter, and it appeared from' it, that it must be a collection 200 Geological Survey of Louisiana [vSect. of small pieces that made up the 14 in. stratum. At 961 ft., we penetrated a stratum that contained water. This stratum was 10 ft. in thickness. We could not tell what the formation of this was, as we took out none of the drillings. The water flowed over the top of the well at this point. There was also a dis- charge of gas from the well that would burn. The water was very strong with salt. I believe this same well was sunk deeper by some other parties after, but what was found below, we do not know." The temperature of the water is 83 ° F. The gas which Mr. Lukins mentions, is collected and used for lighting the office at the ice factory. Coushatta bluffs. — The faint casts oi Leda, Luchia, Nucula, and Venericardia which were found at this bluff, while proving the Eocene age of the material, are not distinctive enough to show exactly the division to which it belongs. The Ledas are however nearer the Lower Claiborne forms than either the Midway or lyignitic forms. The section here shown is : Section, Coushatta blujfs 6. Orange, red, yellow, gray and white sand, stratifica- tion generally horizontal, but in places showing cross-bedding. It contains numerous gray clay gravel and a few thin clay layers. Changing above to surface soil 20 ft. 5. Black clay with thin gray sand partings below becoming light brown above. Layer about eight inches thick and two feet from the base contains faint casts of Leda, Niccnla, Lnchia and Ve7iericardia 10 ft. 4. Very dark brown laminated clay filled with large iron concretions. The concretions are arranged along three principal lines ; at the base, a double layer about 14 feet from the base and a layer at the top. . 20 ft. 3. Black laminated clay, with crystals of gypsum 6 ft. 2. Dark brown sand containing a few thin layers of black clay 3 ft- I. Black laminated sandy clay, showing clay partings and numerous crystals of gypsum, to water level 3 ft. in] Shreveport Area : Archeology 201 Conchisio7is. — The possible occurrence of Lower Claiborne at Shreveport and of Midwa)- at Albany fiats makes the stratigraphy about Shreveport appear much more complicated than had been supposed and it is greatly to be regretted that suits of the samples of the borings of the deep wells in the river bottoms and the deep well at the ice factory have not been saved. It furnishes a flow of warm, artesian water. From this fact it has been supposed that the well has reached the upper part of the Cretaceous.* But it must be confessed that the correlation with the Cretaceous on the basis of salt water furnished is very doubtful. One of the brine springs of Sabine parish, whatever its ultimate source maj- be, flows from the lower Claiborne strata ; the other from presumablj' Lignitic. It is to be hoped that samples will be saved from future wells. Appendix A Catalogue of Aboriginal Works on Caddo Bottoms N. W. % ofS. IV. X. Sec. 4, 20 N.^ 14 W.—^ small, rudely rectangular platform mound about 25 by 30 feet and 10 feet high. On the north side there is an irregular raised platform two to three feet high. The mound has been opened, with a hole about five feet in diameter, by negroes searching for treasure. Sec. §, ig N., 14 IV. — Group of three mounds. They are rudely rectangular, truncated pyramid mounds. The largest is known as " Treasure mound." It is almost square, measuring about 75 feet each way, and is about 16 feet high, ft is com- posed of black, sand)' loam like that beneath the veneer of red clay on the surrounding land. An excavation about six feet square has been made on the eastern side and a pot is reported to have been discovered. A small excavation was started on the- west side but was abandoned before anything was discovered. About 150 feet south of the mound is a "water-hole." This probabl}' represents the excavation from which the material was obtained for the mound. The top of the mound is covered with *Lerch. Bull. La. State Expt. Sta.; Geol. and Agr.,part II, pp. 117, 1893. The engineer at the ice factory reports that it maintains a constant temperature of 83° the year round. A slight flow of gas accompanies the water which is collected and used for lighting the ice factory. 202 Geological Survey of Louisiana [Sect. a growth of white locust and is said to be the only place in the region where it is found. The mound although surrounded by the waters of Sodo lake during the raft period, was not covered. It was used as a place of refuge during the war by persons desir- ous of escaping the conscription officers. "Arick's mound," the second of the series, is rudely rectan- gular, measuring 40 by 50 feet on top, and is 12 feet high. "Youngblood mound" is 6 feet high and about the same dimensions on top as "Arick's mound." A fourth elevation, known as " Trezevent mound," is found in the same group. It is very irregular and appears to be simply a natural elevation. Sec. 21, 22 N., i/f. IV. — Small conical mound on Red bayou ; reported to have been opened. Sec. 75, iS N., 14. W. — Mound between the Pass and Twelve Mile bayou. This mound was not visited but is shown on sheet No. 17 of the Red river survey, 1886. Sec. 2, 21 N., 15 IV. — Two mounds, 200 feet in diameter and 15 feet high on Black bayou, reported by Collins to be natural.* //ale's wood yard. — Artificial mound on top of lower bluff at Hale's wood yard, 100 feet in diameter and seven feet high ; reported by Collins. f Stonny pointy Ferry lake. — A cellar dug near the end of Stormy point by Col. S. D. Pitts in 1885, disclosed quite an amount of pottery at a depth of from four and one-half to five feet. One large pot, when found, was full of living ants, evidently attracted there by something the pot contained. A smaller pot was filled with children's bones. An iron tomahawk, two iron rifle barrels and an iron knife about eight inches long were also found. About 1870 high water washed out the bluff on the southwest- ern corner of the point and exposed a skeleton. The forehead was covered with a thin highly ornamented piece of silver bent to fit the skull. On the back of the head was a circular piece of silver. These pieces are said to have been analyzed by a local jeweler and pronounced virgin silver. On the shoulders were thin crescent shaped pieces of metal. They were described as *43d Cong. 1st Sess., House Ex. Doc, vol. 2, part 2, p. 654. t Ibid, p. 653. Ill] Shreveport Area : Elevations 203 having been coated with green, and are hence inferred to have been copper. The son-in-law of Larking Edwards, the interpreter and friend of the Caddoes, " Old James Shemick," from whom the place was bought, stated several years before the skeleton was found that the last chief of the Caddoes was buried somewhere in that vicinity. This point was a favorite place for the collecting of the Caddo Indians when they desired to start for Shreveport. The}' crossed the lake at Newport point and their trail from there to Shreve- port is said to have been quite visible as late as i860. A Dictionary of Altitudes in Northern Caddo Parish and Adjacent Portions of Bossier Introduction. — The most important lines of levels which have been run in this region are those which were made in connection with the Red river and Cypress bayou surveys by the U. S. Engineers under direction of Maj. J. H. Willard. The closure of the line of precise levels, run by the Red River Survey from Coast and Geodetic Survey P. B. M. No. 215 at Delta, La. by way of Shreveport to Coast and Geodetic Survey P. B. M. No. XLV at Smithland, within 22 millimeters* leaves little doubt of the extreme accuracy of the work. The altitudes given in the following tables and credited to the U. S. E. have been reduced to mean Gulf level from the tables published in the Annual Report of Capt. J. H. Willard for 1893.! A few marked R. R. S. M., have been taken from the maps of the Red River Surve3^ The reduction of the altitudes on the profiles of the various railroads centering at Shreveport to Gulf level has been made possible by a connection of the U. S. E. gauge with the city bench mark at the corner of Crockett and Commerce streets by Mr. Cain, city engineer, Nov. 22, 1898. This showed city elevation 7.18 feet equal to zero U. S. E. gauge. Hence zero city elevation equals 132.83 feet mean tide. * An. Rept. Chief of Eng. for 1893, pp. 1944, 1956. tAn. Rept. Chief of Eng. for 1893, Appendix V. pp. 1953, 1956-57, 1973-74, 1982, 2064, 2o8o-8r, 1893. 204 Gkological Survey of Louisiana [vSect. A connection of the city levels with the levels of the Kansas City, Pittsburg and Gulf Railroad levels made by Mr. H. DeVV. Smith, the company's division engineer, and Mr. Cain showed zero city levels:=22i.9 feet K. C. P. & G. R. R. levels. Hence zero K. C, P. & G. R. R. levels is 89.07 feet below Gulf level. Abbreviations K. C. P. & G. R. R.— Kansas City, Pittsburg and Gulf Rail road. R. R. S. M. — Red River Survey Maps. T. S. & N. R. R.— Texarkana, Shreveport and Natchez Rail road. T. & P. R. R.— Texas and Pacific Railroad. U. S. E. — United States Engineers. nil Shreveport Area : Elevations 205 Locality Authority Elevation Albany, U. S. E. bench mark Ananias station Arkansas-Louisiana line Bargetown slough, high water 1892 . . Beazlev's Landing, benchmark. No. 10. Beckham's branch, K. C. P. &G. R. R. bridge Do bed of branch Black bayou, K. C.,P. & G. R. R.bridge Do bed of branch Blanchard Blankton's bluffs : U. S. E. permanent reference point No. 21 Blankton's, top of bluff onLa.-Ark. line Bossier City, P. R. P., No. 35, yard of Mrs. D. C. Caine Corner plantation, high water 1892. . . . Do U. S. E. bench mark. No. 11 Coushatta bluffs, P. R P., No, 27 Cross lake, south end K. C. P & G. R. R bridge Cross lake, center K. C. P. & G. R. R. bridge Cross lake, bed of outlet channel Do high water, 1892 lilmer's bayou, high water 1892 Eric's plantation, bench mark, No. 13. Ferrv lake, K. C. P. & G. R. R. bridge. ' Do K. C. P. & G. R. R., bed of Ferry lake, K. C. P. & G. R. R., high water 1892 Gilmer landing, bench mark, No. 8. . . . Gold Point plantation, bench mark, No. 14 Hackedv slough (Sec. 36, T. 22, N., R. 15 W.)* Henderson's Mills, bench mark, No. 2 Herndon's landing, bench mark, No. 17. Herndon plantation, per. ref. point, No. 34 Highest point on the K. C. P. & G. R. R , between Shreveport and the State line, center N. E. 'X, S. 20, T. 19, N. R. 15 W Holmes bayou, K. C. P. & G. R. R. bridge r. S. E. K. C. P. K. C. P. U. S. E. U. S. E. & G. R. R. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. Barometer U. S. E. U. 8. E. U. S. E. U. S. E. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. U. S. E. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. U. S. E. T. S. &. N. R. R. U. S. E. U. S. E. U. S. E. K. C. P. & G. R. R. K. C. P. & G. R. R. 226.0 201. 224. 212. 190.0 217. 196. 201. 173- 226. 215.0 335- 173-8 1888 185.4 240.9 181. 180. 152. 177. 203.0 183.7 197. 155. 187. 225.3 181.3 174. 2515 177 7 177 9 323. 201. ♦This elevation is only a rough approximation. Hackedy's slough in the company's levels is 60 feet : where the survey crossed the road a little west of U. S. E. B. M., No. 10, near Rocky Point, the elevation was 76 feet. This gives an approximate correction of 114 feet (190-76). 2o6 Geological Survey of Louisiana [Sect. Locality Authority Elevation Holmes bayou, bed of bayou Hoss * Howard bayou, K. C. P. & G. R. R. bridge Howard bayou, bed of bayou Hurricane bhifls, base per. ref. point, No. 29 Hurricane bluffs, topper, ref point, No. 30a Irving's bluff, base f Do top of hill south of ferry Jeter landing, bench mark Kountz's canal, high water, 1892 I^ake Home plantation, per. ref. point, No. 28a Line creek, K. C. P. & G. R. R. bridge Do bed of creek Louisiana- Arkansas line McLaughlin's branch, K. C. P. & G. R. R. bridge McLaughlin's branch, bed of branch. . Missionary place, high water, 1892. . . . Missionary P. O Mooringsport, bench mark Do K. C. P. & G. R.R. station Do highest point in, on K. C.P. &G. R. R. track. Myrtis station Pandora planta. bench mark. No. 15. . Peru plantation, per. ref. Point, No. 28 Poston's bayou, high water, 1892 Rodessa Roswell Rush Point Do high water, 1892 Shreveport, bench mark in Post-Office yard Shreveport, corner Murphey abd Texas ave Shreveport, high water, May 28, i8q2. . Do Do Do Do Do low water, Nov. 20 1893. . . low water, Dec. r, 1894... south end of V. S. & P. bridge Texas street and K. C. P. & G. R. R. crossing.... top of corporation stone near K. C. P. & G. R. R. shops K. C. P. & G. R. R. T. S. & N. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. U. S. E. Woodruff survey Barometer U. 8. E. U. S. E. U. S. E. K. C. P. & G. R. R. K. C. P. &G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. R. R. S. M. U. S. E. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. U. S. E. U. S. E. K. C. P. & G. R. R. R. R. S. M. R. R. S. M. U. S. E. U. vS. E. Citv engineer U. S. E. U. 8. E. U. 8. E. City engineer K. C. P. & G. R. R. K. C. P. & G. R. R. 186. 249. 192. 182. 194.7 224.8 184. 330. 200.3 210.5 192.6 202. 177. 224. 216. 192. 212.7 208. 186.2 196. 202. 209. 184.2 198.5 208.5 227. 200. 193- 194.3 198.81 261.0 175.7 142.6 145.4 188.34 242. 247. *See note under Hackedy's slough. + Obtained by comparison of data shown on Woodruff survey map with Red River sur- vey charts. It therefore represents only an approximation. Ill] Shreveport Area : Elevations 207 Locality Authority Elevation Shreveport V. S. & P. R. R., and K. C. P. & G. R. R. crossing Shreveport ■water-work standpipe, base Do zero U. S. E. gauge Shreveport Junction, T. & P. R. R. bench mark Slaughter's bayou, K. C. P. & G. R. R. bridge Slaughter's bayou, bed of bayou Soda Fount plantation, bench mark. No. 12 Southside plantation, bench mark, No. 16 Surry P. O Tiger branch, K. C. P. & G. R. R. bridge Tiger branch, bed of branch Do high water Vance's plantation, per. ref. point, No. 31 Vivian Wild Lucia P. O Do high water, 1S92 Willow Bend place, high water, 1892. . . K. C. P. & G. R. R. City Engineer U. 8. E. T. & P. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. U. S. E. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. K. C. P. & G. R. R. U. S. E. K. C. P. & G. R. R. R. R. S. M U. S. E. U. S. E. 235.1 266.9 140.01 230.28 199. 183.6 179.6 205. 190. 163. 188. 180.3 249. 195- 198.0 186.6 2o8 Gkological Survey of Louisiana [Sect. U. S. E. Bench Marks and Permanent Reference Points Shown ON Soir, Map ok Upper Red River Valley. (The elevations here given are taken from the report of Capt. J. H. Willard for 1893, An. Rapt. Chief of Kng. for 1893, Appendix V. The eleva- tions have been reduced to mean Gulf level and are the elevations of the boss of the pipe cap over the bench mark.) P. B.M.INo. I Albany Point Henderson's Mills Mooringsport Jeter Landing B. M. " 8 i Gilmer's Landing, near Dr. Vance's residence. Between Cowhide and Horseshoe bayous Uni Plantation near Irving's bluflF road Corner place on west side of road running south On back levee north end of Soda Fount Plan- tation .... James Eric place S. W. corner Gold Point plantation Levee, Pandora plantation Back levee between Soiith Side and Cuba plan- tations Cuba plantation between Twelve Mile bayou and the river Herndon's landing P. R. P.i " 21 Blankton's bluffs, 500 feet north of Louisiana- Arkansas line West bank, 90 feet south of Bargetowu slough. East bank , head of Boom bend East bank, south side of Alban's canal No. i 450 feet from the river Hast bank, just below Poston's baycu East bank, between Red river and Dutch John's lake Top of Coushatta bluflf Back levee between Peru plantation and Doo- le}''s bayou Back levee, Lake Home plantation Hurricane bluffs, upper end 30a Top Hurricane bluffs 31 j Vance's plantation, near wind-mill 32 North side Benoit's ba5'ou 33 West bank, just above Barr's ferry 34 Herndon plantation %5 Bossier City, yard of Mrs. D. C. Caine B. M. " 45 Shreveport, postoffice yard 3 i 4 i 8 I 9 10 I II 12 13 I 14 i 16 ! i6a| 17 28a 29 226.0 251-5 186.2 200.3 225.3 193-0 190.0 185-4 183.6 183-7 181.3 184.2 179.6 178.2 177.7 215 o 207.9 206.6 204.0 200.8 200.4 240.9 198-5 192 6 194-7 224.8 180.3 184.7 175-6 177.9 173-8 198.81 GROLOGrcAL Survey or I.oi -«ii^' ^^:0' V /• GBOM>CICiU, 8KHTEY OF IXimStANA. P^ITE ANSK ISLAND THIS IS ABOl'T ONi:-HAI.P THK DIMRNSIOXS OF THK MODKL Special Report No. j THE FIVE ISLANDS BY Arthur C. Veatch CONTENTS Introduction Page Page The writer's visit to the Mapping of the islands 213 islands 213 History of the Study of the Islands Period Before the Discovery of Rock Salt Stoddard 213 Darby 214 Thomas sy' s first visit 214 Period Since the Discovery of Rock Salt Thomas sy' s second visit 215 Pomeroy 218 Owen 215 Bolton 218 Goessmann 215 Joor 218 Hilgai'd 215 Lercli and Vaugha7i 218 Lockett, 217 Clendenin 219 Hopkins 217 Lucas 219 Rapley 217 Geographical Position and General Topographi- cal Description of the Islands Geographical Position Location 219 Surronndiyig country 220 General Topography Lsland-like character of the Area 220 hills 220 Elevation 220 Belle Isle Location Geograph ical su rro 21 n dings .221 Topography Shape and area 221 Positio?i of the hills 221 History of the Mining Operations Discovery of salt 222 Present work 222 Geology Surface of geology 223 Analyses of salt 226 The sand pit fossils 223 Limestone in salt 227 The wells 224 Section at the shaft 225 Galena from the shaft 225 Salt 226 Archeology Shell heap 229 Section of hole No. 12 227 Section of hole No. ij 228 Conclusions 229 Cote Blanche Location and Topography Location 229 Topography 229 GeoLOGY Salt investigatio7is 230 Tin ^ea-clij/ section 230 Surface geology 230 Grande Cote Location Methods of communication Surrojoidifig country 231 with the main land 231 Topography Central ridge 232 The lakes 232 History ok Mining Operations Ea rly work 233 Later work 233 Geology Surface geology 234 Origifi of the lakes 234 The wells 234 Conclusio?is 236 The shape and position of the salt mass 234 Archeology Shell heap 237 Petite Anse Location Geographical Position 237 Communication with the Surrounding country 237 tnain land 238 Topography Shape and area 238 The lakes 239 The hills 238 History of Mining Operations Early period: prior to 1862.22,9 Present period : iSdy-iSgg .2\\ War period : 1862-186 j .... 240 Geology Surface geology 243 Section northeast of the mine 24.^ Lignite 244 Vertebrate remains 245 Section at deep boring 244 New shaft sectio7i 247 Sandsto7ie of Iron mine run 244 Analyses of the Salt Yearly production of salt . . . .248 The lakes: a zoological problem 249 Archeology Remains in salt mine valley .251 The salt 247 Marsh fires 249 The cypress stump stratum . . 250 Co7iclusions 250 Other remains 253 C6te Caroline Location and Topography Geographical position 254 Surroti7iding country 254 Geology Stirface geology 255 Bluff section 255 Salt exploratio7is 255 Section of hole No. 8 256 Topography 255 Blue clay ajid zinc 256 Shape of salt mass 256 Co72clusio?is 257 Attakapas Prairie Well Sections Hilgard' s snppositio7i 257 Gle7tcoe well sectio7i 258 feannerette well sectio7i . . . .257 Tho77tassy' s sectio7i 258 Gkxeral Considerations The Origin of the Islands The method and date of Comparison of the Louisiana formation 259 rock salt deposits to the great deposits of the world 261 Ill] Special Report No. 3 : Five Islands 213 THE FIVE ISLANDS Introduction The write f s visit to the islands. — In view of the recent develop- ments, the writer was directed during the spring of the present year to leave work in northern Louisiana and make an examina- tion of the Five Islands in Iberia and St. Mary parishes. Mapping of the Islands. — The lack of accurate maps of the islands was immediately noticed and he at once began making a twenty-foot contour map of Petite Anse island. During the work on Grande Cote, in locating the different prospect holes and in determining their elevation above tide, enough facts were collected to make a sketch topographic map of that island. Belle Isle was also mapped. It is regretted that there was no one on Cote Car- line (or Jeflferson island) who could give information regarding the prospect holes there. It accordingly seemed advisable to post- pone the mapping of this island, for its general features are shown on the maps of the other islands, till such data could be obtained. History of the Study of the Islands Period Before the Discovery of Rock Salt Probably no portion of Louisiana has received more attention from geologists than the central costal region and especially Petite Anse island. The phenomena there shown are of such a character as to attract attention at once. Stoddard. — Although Maj. Stoddard evidently did not visit any of the islands, their existence was known to him. He speaks of the elevated islands along the coast; "some of which" he assures us, " contain sulphur and one has been known to be on fire for at least three months. ' ' To stories of th is nature is doubt- less to be traced the origin of the name " Fire islands" applied to this group.* He describes Belle Isle as about three miles in Sketches of Louisiana by Maj. Stoddard, Phila., 1812, pp. 179-180, 184. * Geology of Lower Louisiana, by E. W. Hilgard. Am. Jour. Sci., 2d Series, voL 47, p. 86. 214 Geological Survey of Louisiana [vSect. circumference, 240 feet high, and situated a few miles west of the mouth of the " Chafalia " river. Darbv. — During or about 1817 William Darby visited Petite Anse. This is, to the best of our knowledge, the first visit of a man of scientific attainments to any of the islands. He was a man of keen insight and may justly be regarded as the first to make geological observations of importance in Louisiana. Darby noticed the marked difference between the flora of the island and that of the surrounding marshes and prairie. The flora he regarded as the same as that on the Opelousas hills and the hills further north. He pointed out the likeness of the salt spring, dis- covered several years before his visit, to the salt springs of Louisiana north of Red river.* This point was not again noticed until Hilgard's third Louisiana article. f He attributes the islands to a source other than the "revolution affected by alluvion." + Thomassy^ s first visit. — Thomassy's first visit to Petite Anse was made in i857.§ Between that time and 1859 he visited all the islands but Belle Isle. He speaks of the salt springs on Petite Anse and traces their origin to masses of rock salt ' ' scattered through the strata." He regards the Five islands and the hills along the Bayou Teche, Boeuf and beyond the Red river as the products of sort of mud, water and gas volcanoes ; in a word they are gigantic mud-lumps. They are not of the same age, Cote Blanche being the oldest and the Cote Gelee, Opelousas and Avoylles hills the most recent. They have probably been form- ing since the middle of the Quaternary. || * The Emigrant's Guide to the Western and Southern States of Louisiana, Mississippi, Tennessee, Kentucky, Ohio, etc. With map. By Wm. Darby ; New York, 181S, p. 86. f Summar}- of Results of a Late Geological Reconnaissance of Louisiana, by E. W. Hilgard. Am. Jour. Sci.. 2d Ser., vol. 48, p. 342, 1869. X A Geographical Description of Louisiana by William Darby, 1816, p. 48. \ Supplement a la Geologic Pratique de la Louisiana. He Petite Anse. Geol. Soc. France, Bull., 2d Series, vol. 20, 1863, p. 542. I Geologic Pratique de la Louisiana par R. Thomassy. New Orleans, i860. Chapter VIII, pp. 72-86. in] Special Report No. 3: Five Islands 215 Period Since the Discovery of Rock Sai,t Thomassy' s seco7id visit. — Shortly after the discovery of rock salt (1862) on Petite Anse he again visited the island, and made a more thorough examination of it. On this visit he found besides the original "crater of elevation," which he mentions in his earlier report, three others. His report* on this visit entitles him to the credit of having been the first to bring the discovery of rock salt before the scientific world and of having prepared the first and most accurate sketch map of the topog- raphy of the island. Owen. — The next scientific observer, and the one to whom the credit of having been the first to make a scientific investiga- tion of the island is generally given, f Dr. Richard Owen, visited the island in November, 1865. After a hasty examination he showed that the island is not of volcanic origin ; but consists entirely of sedimentary material. | The island he considers a dune-like formation made by the combined action of the wind and waves. Goessma7in. — Under the auspices of the American Bureau of Mines, in November, 1866, Dr. Chas. Goessmann, in company with Mr. C. E. Buck, made a careful economic examination of the island and prepared a sketch hacheur map. Goessmann supposes that the rock salt deposit was formed from salt springs rather than sea water, and is of Tertiary origin. § Hilgard. — The following year Prof. Eugene W. Hilgard, under the direction of the Smithsonian Institution, visited the * Supplement a la Geologie Pratique de la Louisiane lie Petite Anse : par M. R. Thotnassy. Carte. Soc. Geol de France, Bull., 2d serie, tome 20, pp. 542-544. 1863. f On the Geology of Lower Louisiana and the Rock Salt Deposit of Petite Anse (abs. ). Am. Jour. Sci., 2d series, vol. 47, p. 77; 1869, by B. W. Hil- gard. Ibid. — Smithsonian Contr. , vol. 23, separate No. 248, p. i, 1872. X On the Rock Salt at New Iberia, Louisiana by Prof. Richard Owen, Trans. Acad. Sci., St. Louis, vol. 2, pp. 250-252, 1868. Ibid. — Am. Jour. Sci., 2d series, vol. 42, pp. 120-123, 1868. § On the Rock Salt Deposit of the Petite Anse, Louisiana, Salt Company. Report of American Bureau of Mines by Chas. Goessmann, New York, 1867. 2i6 Geological Survey of Louisiana [Sect. three central islands. The results of his investigations are embodied in a number of articles.* Before his reconnaissance of western and northwestern Louisi- ana in May and June, 1869, he considered the rock salt as having been formed by evaporation in a lagoon or series of lagoons and as resting in a bed of marine clay similar to that found at New Orleans and Bayou Sale (since correlated with the Port Hudson) and of similar early Quaternary age, anterior to the Orange Sand. During the Orange Sand and Port Hudson deposition the western part of the Mississippi valley was filled to a height equal to if not exceeding that of the highest hills of the islands and in the subsequent erosion of the valley by the Mis- sissippi river these islands were formed by the accidents of differential erosion.]; In November, 1869, Hilgard first advanced the theory of the " back-bone " of Louisiana. This theor}- he re-affirms in his * Preliminary Report of a Geological Reconnaissance of Louisiana New Orleans, 1869. Ue Bow's Review, vol. 37-38, pp. 754-768. Geology of Lower Louisiana and the Rock Salt Deposits of Petite Anse. Am. Jour. Sci., 2d series, vol. 47, pp. 77-88, 1869. Am. Assn. Adv. Sci., Proc, vol. 17, pp. 327-340, 1869. Abstract, Neues Jahrbuch, 1S73, pp. 553-554. 1874. On the Geological History of the Gulf of Mexico. Am. Jour. Sci., 3d series, vol. 2, p. 393, 1871. Am. Assn. Adv. Sci., Proc, vol. 20, 1871. La. State Univ., Report of Supt. for 1871, pp. 207-222, New Orleans, 1872. Am. Nat., vol. 5, pp. 514-518, 1871. (Remarks on the Age of the Rock Salt of Petite Anse.) Am. Nat., voL 5, pp. 523-524, 1871. On the Geology of Lower Louisiana and the Rock Salt Deposits of Petite Anse Island. Smith. Contr., vol. 23, separate No. 248, Washington, 1872. The Salines of Louisiana. Mineral Resources of the U. S. for 1882, pp. 558-565, Wash., 1883. Physico-geographical and agricultural features of the State of Louisiana. Tenth Census U. S., vol. 5, p. 112. f On the Geology of Lower Louisiana and the Rock Salt of Petite Anse by Eugene W. Hilgard, Am Jour. Sci., 2d series, vol. 47, p. 84, 1869. tibid, p. 88. GkoI.OC.ICAI, SlKVEY OK LOUISIANA, KlcrOKT, 1899 JOHN MARSH AVERV, DISCOVERER OK ROCK SALT Geoi^ogicai, Survkv of Louisiana, Report, 1S99 PI.ATR 21 Topoi^raphic Map of Belle Isle By a. C. Veatch Ill] Special Report No. 3: Five Islands 217 later articles. According to this, the Five Islands are but the erosion-formed outliers of a Cretaceous ridge or backbone which traverses Louisiana from its northwest corner in the direction of Vermillion bay ; the salt being of Cretaceous rather than early Quaternary age. He thinks that at the beginning of Tertiary time the existence of the axis of elevation was marked merely by a number of disconnected islands.* In later geological times the five outcrops were buried under deposits of Orange Sand and Port Hudson material, as indeed was the whole Mississippi valley, and in the re-excavation of the valley by the Mississippi the material covering the Cretaceous nuclei was not eroded so much as that of the surrounding countrj', thus forming the islands, t Closely following Hilgard came Lockett of the Louisiana State University. Lockett. — Col. lyockett visited the islands in 1870. He con- sidered them as merely a prolongation of the Cote^ Gelee, Car- encro, Grande Coteau and Opelousas hills ; the whole at one time forming a great natural levee along the shore of a vast estuary occupying the present Mississippi valley. During a great flood a series of mighty crevasses were made in this levee, thus forming the islands. J Hopkins. — So far as we are aware Hopkins did not visit the Five Islands, certainl)- not during the time spent in collecting material for his first three reports. His idea of the structure and relations of the islands to the surrounding terranes is shown in his cross-section of the State republished in the general dis- cussion of the Cretaceous (p. 33). Rapley. — In 1884, in the preparation of an article on the " Soils and Products of Southwestern Louisiana " for the U. S. Department of Agriculture Mr. E. E. Rapley visited Petite Anse * Geological History of the Gulf of Mexico by E. W. Hilgard, Am. Jour. Sci. , 3d Series, vol. 2, pp. 393, 871. f Ibid, p. 404. X Second Annual Report of the Topographical Survey of Louisiana, by Samuel H. Lockett. Louisiana State University, Report of Supt. for 1870, pp. 16-26, New Orleans, 187 1. 2i8 Geological Survey of Louisiana [Sect. and Cote Blanche. He gives a short account of the mining methods on Petite Anse.* Pomeroy. — Pomeroy's report on the islands is confined to a discussion of the methods of mining salt on Petite Anse.f Bolton. — Early in 1888 Dr. H. Carrington Bolton read a paper before the New York Academy of Science on the " Great Salt Deposits of Petite Anse. ' ' He mentions the occurrence of lignite and sandstone north of the shaft in Iron Mine run and concludes from the direction (S. E.) of the dip that it must pass beneath the salt. The black bands in the salt, he states, contain about seven per cent, of insoluble matter chiefly gypsum and form well marked folds, from which he concludes that at some time the salt has been submitted to lateral pressure.;}; Joor. — The discovery of numerous vertebrate remains on Petite Anse in an attempt to sink a shaft in 1890 was the occasion of a visit to the island by Dr. Joseph P". Joor of New Orleans. § Lerch and Vang han. — ^Although neither Eerch nor Vaughan visited the Five Islands their diametrically opposite views on the origin of the various Cretaceous outcrops in the State, based on observations in northern Louisiana early in the present decade, are of interest here. Eerch holds || that they represent the peaks * Bull. U. S. Dept. Agr. The vSoils and Products of Southwestern Louis- iana, including the parishes of Saint Landry, LaFayette, Vermillion, Saint Martin's, Iberia and Saint Mary's (by E. E- Rapley) Washington, Govern- ment Printing Office, 18S4, pp. 36-40. f The Petite Anse Salt Mine, by Richard A. Pomeroy. Eng. and Mining Journal, vol. 46, pp. 280-281, 1888. Sci. Amer. Suppl., vol. 26, pp. 10719-10720, No. 671, 1888. Am. Inst. Mining Eng., Trans., vol. 17, pp. 107-113, 1889. :(:The Great Salt Deposits of Petite Anse by H. Carrington Bolton, New York Acad. Sci., Trans., vol. 7, pp. 122-127, 1888. The Great Salt Deposits of Petite Anse, Louisiana, by H Carrington Bolton. New York Acad. Sci. Trans., vol. 7, pp. 122-127, 1888. Sci. Am., Supp. vol. 26, pp. 10475-10476, No. 656, 1888. Am. Nat. vol. 20, p. 1074, 1886. § Notes on a Collection of Archeological and Geological Specimens Collected in a Trip to Avery's Island (Petite Anse), Feb. ist, 1890, by Joseph F. Joor, M. D., Am. Nat., vol. 29, pp. 394-398, 1895. II A Preliminary Report of the Hills of Louisiana South of the V. S. & P. R. R. to Alexandria, La., by Otto Lerch. Bull. State Expt. Station, La., Part II, p. 72, Baton Rouge, 1892, Ill] Special Report No. 3 : Five Islands 219 of the great mountain chain made of fractured, faulted and folded strata ; while Vaughan thinks that they owe their origin entirely to erosion in pre-Eocene time.^ Clendenin. — W. W. Clendenin, formerly geologist to the State Experiment Station, visited all the islands during 1895. He concludes that the foundation of these islands is Cretaceous and that the Cretaceous ridge, of which the islands are remnants, owes its origin to differential elevation in pre-Eafa3'^ette time ; which differential elevation was continued in the later part of the Lafayette; but that the present aspect of the islands is due to the interruption of this ridge by erosion, which began immediately after the initial elevation and was most active during the early part of the Columbia period. f Lucas. — The latest published observation on the islands are by Capt. A. F. Eucas, at one time superintendent and manager of the Avery Mine and in charge of most of the borings on C6te Carline, Cote Blanche and Belle Isle. He gives abstracts of the Cote Carline Island borings \ and records the discovery of salt on Grande Cote and Belle Island. § He states that the salt is of Tertiary age but gives no reasons for believing it such. Geographical Position and General Topographical Features of the Islands Geographicai. Position Location. — Reference to the geological map of the State will show five elevations along a line bearing S. 49° E. and running from Lake Peigneur, half way between New Iberia and Abbeville, to the mouth of the Atchafalya river. Only one, the second, *A Brief Contribution to the Geolog)- and Paleontology of Northwestern Tyouisiana by T. Wayland Vaughan, U. S. Geol. Survey, Bull. No. 142, p. 15, 1896. f A Preliminary Report on the P'lorida Parishes of East Louisiana and the BluflF, Prairie and Hill Lands of Southwest Louisiana by W. W. Clendenin, La., State Expt. Station Bull. Geology and Agriculture Part III, pp. 239-240, 1896. :j:The Avery Salt Mine and the Joseph Jefferson Salt Deposit, Louisiana, by A. F. Lucas, Eng. and Mining Jour., vol. 62, pp. 463-464, 1896. § Louisiana Salt Resources by A. F. Lucas. Am. Manuf ., vol, 63, pp. 910-91 1, 1898. 220 GEOLO(iICAL SuRVEY OF LOUISIANA [Sect. is on the sea-coast. The others range from an eighth of a mile, in the case of the central elevation, to at least eight miles in the case of the one at the extreme northwest end of the series. All face on one side at least, the waters of a bayou or lake. Stirroundhig country. — The lower four are entirely surrounded by a great sea marsh, much of which during extremely high tides, occasioned by strong south winds, is covered with water. The upper one rises abruptly from a very level prairie. In order, from the most southeastern, they are Belle Isle, C6te Blanche, Grand Cote, Petite Anse and Cote Carline. General Topography Island-like character of the hills. — It will be readily seen that in the ordinary sense these are not islands, but there is very lit- tle difficulty in seeing why the lower four were called such. The isolated, island-like character of these groups of hills ; their separation from the main land by impassible sea marsh and cypress swamp ; the fact that they offer to man a place for houses and fields and the surrounding land does not ; all tend to make the resemblance of these isolated clusters of hills to ordinary islands very marked indeed. The term would then naturally attach itself to the analogous group of hills. Cote Car- line, rising abruptly out of the prairie. Area. — The largest island, Grande Cote, is an irregular circle a trifle over two miles in diameter ; the longest. Petite Anse, has an extreme length of about two and three-eighths miles. The former has an area of a little less than 2,000 acres ; Cote Carline, the smallest, has only about 300 acres.* Elevation. — While an elevation of 75 feet, the elevation of the highest hill on Cote Carline, or even twice as much, the eleva- tion of Prospect hill Petite Anse, in some regions would be a very insignificant feature indeed, hills of this size rising abruptly out of the perfectly flat sea marsh attract attention at once.t * Lucas. Am. Manuf., vol. 63, p. 910. 1898. t Both the areas and the altitudes have been the subjects of a great variety of statements, by diflferent authors. Many are merely estimates. Some, in the case of land areas, are based upon deeds which describe land situated not only on the island but in the surrounding marshes. Thus the area of Ill] The Five Islands: Belle Isle 221 Bei-le Isle Location Geographical surroiuidiyigs. — Near the mouth of Myrtle bayou, one of the distributaries of the Atchafalya and about eight miles from the mouth of that river, surrounded by a network of bayous and impassible sea marsh is Belle Isle. Mj^rtle bayou is a quarter of a mile from the islands but two little deep bayous pass along the island, one on the eastern and one on the western side. On the south is a small shallow lake, Belle Isle lake, about half a mile long and a quarter as broad, with a tiny little marshy island near the northern end ; and a mile over the marshes is the shore of Atchafalaya bay, an arm of the Gulf. (See plate 21.) Topography Shape and area. — The general shape and immediate surround- ings of Belle Isle are shown on the topographical map of the island (PI. 21). The island, that is, the portion above the sea marsh, has an area of 360 acres, barely half of which is now in cultivation. Position of the hills. — The island is a rudely triangular area with a single range of hills along its north-west side. This range shows four peaks. The highest, " Lookout hill," on the Cote Carline is given in one place as 300 acres and in another 9,000 acres. Most of the elevations are based on barometric readings, though some are merely guesses. Belle Isle is given as more than 200 feet high by Maj. Stoddard (Sketches of Louisiana, Phila. 1812, p. 179); 85 feet by Hilgard (Mineral Resources of the U. S. for 1882, p. 558); and 125 by Clendenin (Bull. La. State Expt. Stations, 1896. On the Florida Parishes, etc., p. 240). It is regretted that on account of lack of time and instruments it was impos- sible to do exact leveling this year, but it is believed that the results obtained in altitudes are accurate to within five feet. Leveling was done with a Locke's hand level, all levels being run at least twice from different points on the nearest bayou, and repeated if the results showed a discrepancy greater than five feet. Locations were made with a 3>^ inch, open siglit, Keuffel & Esser compass. While great precision is impossible with these instruments, it is believed that the results will advance our knowledge at least one step toward a satisfactory degree of refinement. 222 ' Geological Survey of L,ouIvSiana [Sect. westernmost point of the island is 80 feet high. It derives its name from the U. S. Coast and Geodetic triangulation platform on its summit. The second, "Green Tree hill," is merely a spur of Lookout hill. Near the giant live oak on one side of its summit is a bit of crumbling masonry which is pointed out as the ruins of the chimney of the house of Lafitte, the pirate. Around it many holes have been dug in a fruitless search for hidden treasure. " Bald hill," 67 feet high, and the Shaft hill, 51 feet high near the northeastern point of the island complete the range. The rest of the island is a gently sloping, slightly elevated ridge which extends south-east from the hills. Willow pond, almost in the center of the island is a shallow, wooded, fresh water pond. History of Mining Operations Discovery of salt. — The accidental discovery of rock salt in" an artesian boring on Cote Carline, and the ever increasing difficulty of mining salt on Petite Anse, due to water in the mine, caused systematic explorations for salt to be begun on the other islands. In November, 1896, Capt. A. F. Lucas undertook, at his own expense, to find salt on Belle Isle. In December he discovered salt in hole No. i at a depth of 373 feet.* In 1897 and 1898 the Gulf company bored additional holes and in August started a shaft on the site of hole No. 11 where the salt was found within 103 feet of the surface. Present work. — With the beginning of work on the shaft the Gulf company put up a large saw-mill plant and has with it cut all the timber for its buildings. To the saw mill has been added a small machine-shop and a barrel-factory. To facilitate trans- portation a short canal has been dug from Myrtle bayou along the eastern side of the island. At the time of the writer's visit, it had reached the southern end of the shaft building and it was proposed to extend it past the saw mill to the site of the evapo- rating plant and storehouse. Wax and Doctor's bayous give deep water communication with the Atchafalya and the Atchafalya afford a fair depth of water both to the Mississippi and to the Gulf. * Letter from Capt. A. F. Lucas. ni] The Five Islands : Belle Isle -223 It is proposed besides mining the rock salt to make a fine grade of table salt by artificial evaporation and to that end a large plant is to be erected south of the saw-mill. The company has purchased a tug and two steamboats and with the construction of the floating elevators it proposes to build, will soon become a very active factor in the salt market Geology Surface geology. — With the exception of a little area on the eastern side of Shaft hill the whole island is covered with grayish yellow to yellowish brown clay. The clay is particularly well developed on the western part of the island. Southeast of Willow pond quite a number of springs ooze out of the ground. This patch of ground though well elevated above the sea marsh is covered with salt grasses. A spring which was situated south of the Shaft house, where the saw-mill now stands was regarded with high faver by the inhabitants on account of a medicinal oil which it produced. On the eastern slope of Shaft hill are small outcrops of a gray, iron stained, rather soft, broken, barytic limestone, which occa- sionally shows galena and chalcopyrite. This is doubtless the crumbled or shattered limestone which Thomassy mentions* and which Hilgard correlated with the Cote Blanche concretions. f It is evidently quite different from the concretions. This lime- stone is well exposed in a number of pits dug several years ago by the U. S. Engineers in an attempt to find stone suitable for jetty work. Near by, sand and gravel come to the surface. The gravel has been dug for concrete work around the works. The sand pit fossils. — About 150 yards from this outcrop a sand pit shows a very interesting section, with fossils. The material dips about 23°, north 15° west. * Geologic Pratique, p. So. f Am. Jour. Sci., 2d Series, vol. 47, p. 85, 1869 ; Smith. Contr., vol, 23, separate No. 248, p. 20, 1892. 224 Geological Survey of Louisiana [Sect. Sand Pit Section. (Elevation of top of section 22 feet A. T. ) I'eet In 1. Surface soil. Dark humus stained cla}' o 6 2. Mottled gray to yellowish brown clay 2 6 3. Mottled gray and brown clay grading below into finely laminated gray clay 4-7 o 4. Massive dark gray clay i o 5. Black clay with iron pyrite 1-3 o 6. Black shell conglomerate o 8 7. Irregular bedded brown to white sand with clay pockets and traces of sulphur 2-5 o The fossils in layer 6 are very poorly preserved but so far as they can be identified indicate a cold water fauna different from the warm water fauna of the Pliocene. All species seem to be represented on the Gulf coast to-day and we are inclined to regard it as Pleistocene although it approaches some phases of the Chesapeake Miocene rather closely. The following is a list of species : Ostrea virginica, Corbula sp. Lithopaga, cf. caiidigera, Mactra sp. Scapharca transversa, Luciyia sp. Gnathodon cjnieatus, Vetius ca7icellata, Dosinia sp. Semelc truncata, Cardiuni rniiricatum, Fnlgiir canalictilatuni. The wells. — A fairly complete idea of the substructure of the island may be gained from the records of the thirteen holes drilled on the island. Eight of these are given on the adjoining (Plate 22).* In hole number 10 gas was struck at a depth of *A11 the facts we possess regarding the other five holes are as follows : 2. Quicksand 400 feet. 3. Salt at a depth of 276 feet. 5. 200 feet deep. No salt. 8. Sand 175 feet. No salt. 9. 0-248. No record 248 feet. 248-500. Salt 252 feet. 500-748. Salt crystals 248 feet. The records of all the sections shown on Plate 22 and also hole No. 9 were obtained from Mr. C. B. Weiser of the Gulf company. The others are from Capt. A. V . Ivucas, who supterintended the drilling. GEOI^OGICAI. SuRVKY of LotJISIANA, Rkport, [899 r^" 1 4 6 7 10 ShaH Pirate 22 12 13 - 10 - 20 '& i:f^ i fi Sri l^g ^? » LEGEND Sand Sand and gravel Gravel Gravel and clay Clay Blue clay t3_^.3^ Black shaly claj' 1 ^, I .Rarite, splialenle, galena l ~ " I and limestone bowlders ^^fjj Haritic limestone [^^^ Salt and clay ;> . /J Salt and black shaly clay Belle Isle M^cll Sections Geological Survey of Louisiana, Rkport,'i899 Plate 23 GALENA (Belle Isle) ROCK SALT (Belle Ible) SPHALERITE (Belle Isle) CRYSTALLINE SALT (Petite Aiise) IMPURE ROCK SALT (Belle Isle) N o. Depths I O- 4 2 4- 13 3 13- 30 4 30- 40 5 40- 63 6 63- 68 in] The Five Islands : Belle Isle 225 1 20 feet in suflficient quantities to throw sand all over the derrick. It is now bubbling out the hole where it can be easily collected and ignited. A small amount of gas and oil was struck in hole number four. The last three are probably of greater interest than the others. Sedioji at the shaft. — The shaft was siink on the site of hole 1 1 so we can feel quite sure of the material there. Shaft (Elevation above tide 7 feet) Feet In. Clay 4 o Hard sand 9 o Blue clay 17 o Blue clay and sand 10 o Hard clay and gravel 23 o Blue clay with crystalline masses, from the size of marble to a man's head, of baryte, galena, sphalerite, pyrite and chalcopyrite 5 o 7. 68- 95 Blue clay and shells 27 o 8- 95- 96/13 Rock. Impure black limestone and baryte i 6 9. 96^-103 Blue clay with masses of baryte near the base 6 6 10. 103-116 Dark colored clay with large salt crystals 14 o 11. 1 1 6-1 1 7 Dark colored clay with oil i o 12. 117-142 Salt with dark colored clay 25 o 13. 142-162 Discolored salt 35 o 14. 162-163 White limestone o 8 15. 163-175* Dirty salt becoming white 12 o Galena fro772 shaft. — The occurrence of galena and associated minerals here is even more surprising than the occurrence of rock salt. It adds another locality to the lead deposits of the Missis- sippi valley. The crystals are all sharp and show no signs of *This was the depth of the shaft at the time of the writer's departure, May 19, 1899. O 226 Geological Survey of Louisiana [Sect, erosion. (See IMate 23.) Numerous pieces were scattered over the dump at the time of the writer's visit. Dr. A. C. Gill, of Cornell University, who has very kindly examined and identified the specimens collected, states that the galena shows no silver, which is common in vein deposits, and that it therefore seems more probable that this represents a deposition from sea water by chemical action. The manner of occurrence, scattered through a bed of blue clay, strongly emphasizes this conclusion. Numerous finds of galena are reported from different parts of the State especially in the northern parishes. These when looked into, have always shown that the lead was not in situ but had, without a reasonable doubt, been carried there by the Indians. Such an explanation will not apply to this deposit. Salt. — The salt occurs in several forms ; large transparent crystals one to eight or more inches long, either in masses, where interference has prevented the formation of perfect cr3'stals or scattered through dark colored clay, as in the upper part of the salt mass ; smaller crystals in masses having the appearance of rather coarse crushed ice or inclosing pieces of dark colored clay which gives the salt a dirty earth-like appearance. Occasionally the large salt crystals show crystals of gypsum. Unlike any of the other islands the salt when first struck on Belle Isle is very impure ; its purity seeming to increase with the depth. The black material which is abundant enough in the upper part of the salt to color the whole mass and which shows some traces of oil, brings to mind the thin black bands in the Petite Anse salt. The resemblance is further heightened by the fact that the black salt on Petite Anse shows about seven per cent, of insoluble matter, part of which is gypsum* and the Belle Isle black salt shows about the same amount of insoluble matter, part of which, although a much smaller part, is gypsum. Analyses of salt. — Two samples of salt from Belle Isle have been analyzed under direction of Mr. R. E. Blouin of the Experi- ment Stations. To these records we have added for the purpose of comparison three analyses of salt produced by evaporation of sea water. *Notes on the Great Salt Deposit of Petite Anse, Louisiana (Abstract) by Dr. H. C. Bolton. New York Acad. Sci. Trans., vol. 6, p. 125, 1888. Ill] The Five Islands : Belle Isle Analyses of Salt. 227 Black salt Belle Isle Layer 12 (120 ft.) White salt Belle Isle (175 ft.) Setubal or St. Ubes, Portugal (Henry). Turk's Island, West Indies (Cook). Martha's Vineyard, Mass. (Goess- mann). Sodium chloride 92.750 .201 .067 .837 1.804 .500 3-325 96405 3-051 .074 .226 -025 -059 96.00 2.35 -30 .45 96.76 1.56 .14 .64 94-71 1.42 .24 •19 3-24 Calcium sulphate Magnesium chloride Magnesium sulphate Magnesium carbonate Sodium carbonate Sodium sulphate Calcium carbonate Calcium chloride Ferric and Aluminic Oxides (Fe, 0, and Al, OJ Water. .: "... •90 .90 Insoluble matter These analyses show a marked difference between the black and white salt of Belle Isle and a close similarity between the white salt and salt obtained from sea water by evaporation. Limestone in salt. — The white chalk-like limestone, eight inches thick struck 74 feet below the top of the salt shows no traces of organic remains. It is composed of extremely small globular grains, like an oolite, only the grains are much smaller. The presence of a limestone of this type in the midst of a salt deposit possibly indicates a continental movement of considerable mag- nitude during the deposition of the salt. Section of hole No. 12. About 150 yards northwest of the shaft and near the old U. S. Engineers pits in hole 12. It is ten feet higher than the shaft. Hole No. 12. Depths Feet 0-12 Clay and sandy barytic limestone : 12 12-21 Blue clay g 21- 53 Blue clay with indurate dark colored clay 32 53- 80 Dark colored clay 27 80-103 Dark colored clay with hard bands 33 103-130 Dark colored clay 21 1 30-1 3 1 Hard bowlder (probably similar to 6 of the shaft section) i 131-138 Dark colored clay 7 138-213 Salt with dark colored clay 75 No. I 2 3 4 5 6 7 228 Geological Survey of Louisiana [Sect. Section of hole No. ij. — Fossils were found in two layers of hole No. 13 which was sunk a short distance north of Willow pond. Section of Hole No. /j. Depths 1^'eet o-ioo Clay 100 1 00- 1 30 Sand 30 130-135 Clay and shells 5 135-145 Sand 10 145-150 Hard clay and shells 5 1 50-200 Sand 50 200-2 16 V^ery hard gravel 16 2 1 6-2 5o Hard sand and gravel . 54 No I 2 3 4 5 6 7 -*-^*.^,^^.s-*— ^ i^TA Galena, sphalerite and barite bowlders £^ Salt'' -^ ■■ 7000 ^ TZOO Fig. ^—Section cross Belle Isle, along line A-B, pi. 20. Conclusions. — All the data collected, while throwing little or no light on the age of the salt deposit and further complicating the questions involved by the introduction of a deposit of galena, baryte and sphalerite have afforded rather satisfactory evidence on the manner of the formation of Belle Isle. A map showing the contour of the salt, constructed on data furnished by the drill holes, shows an oblong dome-shaped mass, longest along its northeast and southwest axis, having just the same trend as the hills ; but differing from the hills in the fact that the dome of the salt is situated on the northeast of the island. (See plate 24. ) The shaft shows clearly that this dome shape is due to uplift and not erosion. When the salt was first struck in the shaft it liij The Five Islands : Cote Blanche 229 was in the form of a distinct anticline and although the shaft has not followed the dome of the anticline exactly, it being now on one. side of the shaft and now on the other, its presence was always clearly indicated. A cross-section of the island from A-B, Plate 21, made by connecting the data furnished by the shaft, the different wells along the line of the section, and the surface outcrops show a very distinct anticline, or better, elongated dome (Fig. 6). It is interesting to note the similarity of the dip of the shell layer and that of the salt. This would seem to fix the time of uplift. The shells are all species now living in the Gulf. They may be regarded as representing the marine facies of the Port Hudson of Hilgard. This would indicate that in very recent time the Gulf coast has been the scene of crustal movements. Archeology Shell heap. — Excavations for a canal near the shaft on the northeastern corner of the island, have revealed just in the edge of the present sea-marsh and covered by from one to three feet of its deposits a kitchen-midden or kitchen refuse heap composed of shells of Gnathodon cuneatus, Ostrea virginica, an occasional representative of the Uyiionidce and vertebrate remains. As exposed along the side of the canal the heap is 150 to 200 feet long and three feet thick. A human skeleton was taken out near the northern end. The most interesting feature of the shell heap are the numer- ous little baked clay objects found scattered through it. Frag- ments of pottery are relatively scarce. These little objects average about two inches in diameter. A common form has the shape of two cones placed base to base. This pattern is varied by making four indentations around its equator. Others are irregular spheres with four elongated indentations about them medially. The way thej^ fit in the hand and their shape would suggest that they were used in playing some game. The location of the mound on the edge of the marsh and not on the island or the edge of some bayou and its being covered with marsh deposits, would seem to indicate that the subsidence which has been progressing on the Gulf coast for the last period is still going on at a fairly rapid rate. 230 Geologicai. Survey of Louisiana [Sect. C6te Blanche Location and Topography Location. — Although not the central island, C6te Blanche, or "Cap Blanche" of the early Spanish cartographers, occupies the geographical center of the Five Islands. It is near the center of the north shore of C6te Blanche bay in township 15 south, range 5 east. Access is had to the island by means of a raised dirt-way leading through the marsh from the land of Cypremort point. Topography . — Cote Blanche is nearl}' circular and in point of size is the third of the islands, having an area of 1400 acres. On one side the waves of Cote Blanche bay have formed a bluff about fift}^ feet high. To this wave-formed bluff is probably due the earh' appearance of this island on the Spanish maps. It is much less rugged than either Petite Anse or Grande Cote. The deep V-shaped hollows of the centers of those two islands are entirely wanting here. On the south side, east of the bluff, a long arm of sea-marsh runs up into the island. Rising abruptly from this is Oak hill the highest hill on the island.* North of Oak hill is a shallow depression in the tops of the hills which was pointed out as the bed of Clear lake. Time was when this was a small pond something like 300 feet in diameter and 3 feet deep. This is the onh^ trace of a natural pond on Cote Blanche. Geology Salt investigations. — The recent salt excitement which has caused the deposits of the islands to be investigated has not yet had its effect on Cote Blanche. A recent letter from Mr. F. F. Myles reports that he intends to prospect the island in the near future. Immediately after the discovery of salt on Petite Anse in 1862 numerous shallow pits were sunk on the island in a vain search for salt. There can hardly be any doubt that the salt is there. All that is required is deep wells. Surface geology. — The lack of rugose topography and well sec- tions renders the exact information on the geology of the island *No altitude determinations were made here, but at the time the writers estimated it as about icx) feet. Hilgard (Smith Contr. No. 248 p. 10) gives it as 180 feet on authority of the coast survey-. Ill] The Five Islands : Graxd Cote 231 not quite so full as could be desired. There are but two sources of such information ; the sea-cliff and an artesian well near the sugar house. The surface is composed almost entirelj^ of brown- ish yellow loani}" cla^-. At one point near the northeast end of the island a gully exposes a little rather cla^'C}- sand with some gravel scattered through it. The sea-cliff sectio7i. — The sea- cliff section has changed since Hilgard's visit in 1869 as one would naturally expect ; the con- stant encroachment of the waves on the land would exhibit differ- ent portions of the same beds and in such irregularly bedded material a fairly marked change maj- be looked for. ^ Section at Sea- cliff Feet. 1. Light yellow surface clay, contains some lime 11 2. Green or blush-green cla^' i 3. Reddish, greasy looking joint clay with many lime- stone concretions 7-8 4. Very fine light red silt with thin claj^ partings about every six inches. Looks like successive flood depos- its as seen on the banks of Red river 11 5. Same as above but with more clay 15 6. Gra^ash 5^ellow clay eroded in irregular forms by the waves to water level 2 No trace of fresh water shells could be found. Particles of vegetable matter could be seen in several layers, particularly in the lower part of laj^er six. Quite a number of the calcareous concretions which cover the beach were broken open in a search for fossils. Off the southwest corner of the bluff numerous stumps and trunks of trees are seen, ranging all the wa}^ from the tree w^hich has just fallen in from a recent cave of the bank to the old remnants which have been battling with the waves for man3^3^ears. Unfortunateh' the data from the Sugar house well are not ac- cessible at present. Grande C6te I/OCATION Methods of commu7iication with the main land. — Until the early sixties the only way to reach Grande Cote or (Weeks' Island) from the main land was by a canoe through Week's bayou from Prairie Au Large below New Iberia. All the products of the 232 Gkological Survey of Louisiana [Sect. island were shipped by light-draught schooners which could enter the bay. Finally, at a very considerable expense, Mr. Weeks con- nected the island with the main land of Cypremort Point by a raised dirt-way. This rendered access to the island much easier. Surrounding country. — The island overlooks, on its western side, an arm of Vermillion bay called Weeks' ba5^ Two bayous approach the island near enough to 'furnish convenient landing places. Near the southwestern corner of the island, Garrett's bayou is within a hundred yards of the timber. The largest bayou and the one which affords the best landing place is Weeks' bayou near the northwest corner of the island. It is probably more than three hundred feet across and quite deep. Were it not for the shallowness of Vermillion bay, w^hich prevents the passage of vessels of even moderate draught, water transportation of the salt would be quite feasible. Here is the remains of an old pier, a relic of the days when water transportation was the onl}' thing possible. This bayou skirts the island for a little over a quarter of a mile then turns northw^estern and finally south- westward into Vermillion bay. On three sides of the island is a trembling sea marsh ; on the eastern side is a swamp which with- out the "causeway '" would be utterly impassible. Topography Shape and area. — Grande Cote is almost circular with an indentation in the shore line on either side a little above the center. The area as shown by the land office records is 1907.69 acres. It is the largest of the islands. Central ridge. — The "Devil's Backbone," the principle topo- graphical feature, extends north from the mine store to near boring No. 2, thus occupying the central part of the island and having a general trend a little east of north. The slopes of the gullies on either side of this dividing ridge are almost perpen- dicular and from 20 to 60 feet in height. Occasionally the divide is no wider than a wagon bed and near the northern end is almost severed in two or three places. Tliis ridge is from 100 to 135 feet high and contains the highest point on the island. From the mine store it turns eastward and then northward giving the whole ridge the shape of a fishhook (Plate 25). The lakes. — In the space thus inclosed by steep hills is Lake Geological Survkv of Louisiana, Report, 1899 Plate 24 Contour Map of the Salt [deposit on Belle Isle. Iilevalion given infect beloiv Gulf Level By a. C. Veatch Xi>fi^-f^.^ O.KOl.OC-.ICAl. Sl'RVKV OK LOUISIANA, RUPORT. I M99 ■rupi>!:tii/>liii Sketch Map of Uraiulc I oU liv A. C. Vkatch Geological Survey of Louisiana, Report, iS ^ ^ ^ ^ u. L E G E N n [,;. , ; I Sand [\^ Sand and gravel ^ Oiavd [|-V-T^ Blue clay p=^ rj Sand and clay h^H Lignite Ei3 Salt Plate 27 1 13 Gra>:de Citt "W/ 5frf;o„i Ill] The Five Islands : Grande Cote 233 valley. This is a small, comparatively level plain about 35 feet above tide. It now contains three wooded lakes, remnants of a much larger one which has been partially destroyed by the down-cutting of the outlet. The most northern of these little lakes is 660 yards long and a fourth as broad. It was reported to be bottomless but careful soundings showed a very gentlj^ sloping bottom nowhere more than eight feet deep. The edge is fringed with reeds and trees but the center is open. There are two other natural ponds on the island : one near the sugar house, Sugar House pond, has had its level raised about two feet by a dam. Its depth is about the same as the larger one in Lake valley. It is situated in the pit of a great amphitheatre. The other, Lily pond, is near the Weeks residence and like the others occupies the pit of an amphitheatre of rather low hills. HisTORV OF Mining Operations Early 7vork. — Sharing with the other islands the excitement produced by the discovery of rock-salt on Petite Anse in 1862 and further stimulated by the high price of salt at that time a few wells were dug in search of salt, but without success. Later zvork. — Following the discovery of salt on Cote Carline in 1895 and on Belle Isle in 1896, Mr. F. F. Myles undertook the exploration of Grande Cote as a private enterprise. In March 1897 with Mr. N. Conrad in charge of the drilling he started the first hole near the sugar house. Conrad drilled five holes, reporting salt in the fourth at a depth of 276 feet, June 25, 1897. In July, the same year, Capt. A. F. Lucas who oversaw the work on Cote Carline and Belle Isle was put in charge. He struck salt in well No. 7 at a depth of 205 feet late in August. In all, fourteen holes were drilled in this preliminary examination. In March i8g8 the Myles Salt company was organized and fourteen additional holes were drilled under the direction of Mr. Geo. Cowie, to determine the best location for a shaft. In July 1898, it was started on the site of hole No. 24 where the salt approached nearest the surface. After a great deal of trouble with quicksand and by employing a portion of the large, sectioned tubing made to penetrate the quicksand overlying the sulphur deposit of Calcasieu the shaft had, at the time of the writer's visit, reached the salt. The 234 Geological Survey of Louisiana [Sect. diflSculty then, on account of the dissoluble nature of the salt, was to make a watertight joint between the tubing and the salt. As soon as this is accomplished the intention is to erect the shaft house and build a switch from the Cypremort branch of the Southern Pacific. Geology Surface geology. — Like Cote Blanche nearly the whole of the island is covered with a brownish yellow soil. In places, notably in the deep gorges along the Devil's Backbone and indeed in nearly all hollows going into Lake valley the upper stratum of clay has been cut through exposing the underlying sands, and sometimes gravel. Kast of the larger lake is a sandpit which furnishes sand for the surrounding country. Springs are com- mon on the Northern slopes of the island. The wells. — The twenty-eight well sections (shown on Plates 27 and 28) show very little variety in the subterranean structure of the island. There is commonly a surface layer of clay from a few inches to 30 or 40 feet thick and then sand and gravel down to the salt. In two wells No. 9 and No. 17 layers of lignite, five feet thick in the first and three feet in the second, were struck just above the salt. In many of the wells the hydrostatic pressure is sufficient to force the water almost to the surface and in well No. 6 it is sufficient to lift the water above the top of the pipe and form a flowing well. The shape and position of the salt mass. — The salt on Grande Cote forms an elongate dome, longest along its north and south diameter (Plate 29). It occupies the western side of the island and appears to extend a little west of the main ridge. No borings have been made along the ridge so that we can not positively say that the salt does not extend in that direction. Well No. 2 did not find salt at 212 feet but no borings have been made between it and No. 9. Whether the dome shape of the salt, well shown by Plate 29 and the cross-sections of the island Plate 30, really indicate a dome or whether its present shape is due to the erosion of the edge of an upturned fault block or to the erosion undisturbed material, could n6t be determined in any direct man- ner. All data collected would however tend to disprove the last supposition. The shaft, at the time of the writer's visit, had not ni] The Five Islands : Grand Cote 235 entered the salt far enough to determine the direction and intensity of the dip. Origin 0/ the lakes. — Thomassy in his visit to the island noticed the upland lakes. Sugar House pond he considered the "orifice where the h3'drothermal forces made their principal eruption;" the others are craters of depression similar to those which have given rise to the numerous little lakes of southern Louisiana,* In the light of our present knowledge of the islands this expla- nation can hardly be accepted, for the phenomena shown here cannot be confounded with that exhibited by the mud-volcanoes of the passes of the Mississippi. The similarity in all these lake basins point to a common origin. The observed facts would point to four different ways in which the lakes might have been formed : (i) by faulting or landslips produced by orographic movements, (2) by faulting or landslips produced by the removal of the salt by subterranean waters, (3) by the formation of sink holes like those of limestone regions and the subsequent stopping of the basal outlet, (4) by the irregu- lar filling of antecedent drainage channels by Columbia loam. Landslips in the sands and clays occasioned by the folding or faulting of the salt bed, even with the aid of subsequent erosion, would hardly be likely to produce the rounded amphitheatre- shaped lake valleys. Many of the local faults, anticlines and sink holes in northern New York have been formed in the second way by the removal of the soluble matter from the beds of the Onondaga salt and waterlime groups by subterranean waters coming from a distance. It is possible, though hardly probable, that the lake valleys on the islands have been formed in the same way. The lack of continuous layers of impervious strata to confine and conduct the underground waters would .strongly oppose this theory. The third necessitates the assumption of a very marked subsi- dence in the region in ver}- recent times, an assumption which is supported by the partiall}'- drowned stream channels of the coastal regions. If the salt mass was elevated well above the sea, say 200 to 500 feet above its present level, water percolating down from the surface of the island would dissolve the salt and * Geologic Pratique de la Louisiana, p. 82, i860. 236 Geological Survey of Louisiana [Sect. emerge in the form of salt springs at or near sea-level. The removal of the salt by water would form caverns. Dirt and sand would naturalh' be carried by the water into these caverns in the salt and finally a large funnel-shaped opening would be produced on the surface. Such sink holes are common in limestone regions and quite a number have been verj- recently produced artificialh' on Petite Anse. The galleries and rooms hollowed out by man in mining the salt correspond to the caverns which would have been produced by water if the salt were elevated enough to give the water an outlet above sea-level. Water run- ning into these chambers through natural crevices in the salt would soon enlarge them to good sized holes when the dirt and sand and gravel would follow giving rise to a great funnel-shaped opening which would tend to enlarge with ever}' succeeding rain. As the water is kept pumped out of the mine the effect is the same as if the salt stood 90 or 100 feet higher. Now, if a subsidence should occur, the chambers and caverns would become clogged with sand and gravel and cla}' because of the diminished velocity of the waters. The material washed down from the steep sides of the sink hole would tend to fill it and if there was a considerable amount of clay in the material the subterranean outlet would become effectually stopped. Water would accumulate in the depression till it reached the lowest point in the surrounding rim of hills, flow over and begin to destroy itself by cutting down the outlet. This second stage is shown in only one of the holes near the mine on Petite Anse. This one, which is northeast of the shaft, has become clogged with clay even though the subterranean channels are still open and a little pond has formed in its bottom. Lakes formed outside of the glacial limits by the irregular filling of a valley by loess, where the latter seemed to collect in the form of a great levee across the mouih of a valley, have been noticed by the writer in southern Indiana.* No trace of such a structure was observed here, and further the lakes have neither the shape nor appearance of a dammed valley, the upper end being commonly larger than the lower. * Notes on the Ohio Valley in Southern Indiana. Jour, of Geol. vol. 6, p. 262, 1898. in] The Five Islands : Petite Anse 237 Conclusions. — Grande Cote shows the same mantle of loamy clav that appears on Cote Blanche although erosion has pro- gressed a little further on the former, due to the formation of sink-holes and the increased gradients thus given the side streams. The lakes seem to represent old sink-holes formed at a time when the land stood higher than now and whose clogging is the result of the subsidence now progressing on the Gulf coast. From what little salt has been taken out of the shaft and from the drill holes, the top layer of impure salt found on Belle Isle seems to be lacking on Grand Cote. This is a point to be taken into consideration in any theory explaining the origin of the dome-shape of the salt mass. ARCHE01.0GY Shell heap. — The most interesting archeological feature of the island is the shell heap on Wrecks' bayou near the landing place just at the edge of the island. This was first noticed by Thomassy.* It is 600 feet long between 30 and 60 feet broad and 10 feet high. The southern end has the shape of a truncated pyra- mid from which a narrow ridge, gradually increasing in width, extends to the northern end of the mound, which is almost as wide as the southern. The heap is composed almost entirely of the common coast Gnathodon. A few animal bones, oysters and pot-shreds are found scattered through the mass. Near the northern end numerous skeletons have been found. Petite Anse LOCATION Geographical position. — Petite Anse island, Thomas' island, t Marsh's island. Salt island or Avery's island, as it has been called in succession, is situated in township 13 south, range 5 and 6 east of the Louisiana prime meridian. It is about ten miles south-southwest of New Iberia in Iberia parish and three miles from the shores of Vermillion bay. Surrounding Country. — Like all the islands we have thus far * Geologic Pratique de la Louisiane p. 82. + The History and Geography of the Mississippi A'alley, to which is appended a Condensed Physical Geography of the Atlantic United States and the whole of the American Continent, 2d Edition by Timothy Flint vol, I, p. 253, 1832. 238 Geological Survey of Loulsiana [Sect. discussed, Petite Anse is entirely surrounded by marsh and swamp land. On the east and southeast, is a large cypress swamp ; a continuation of the Cypremort swamp. The level sea marsh gives an unobstructed view of the prairies on the main land and on clear days, of the Gulf waters. The western side of the island is skirted by the Bayou Petite Anse. Here is the landing, the boat-house and the old piers used for shipping sugar and salt ; for Petite Anse was important first as a sugar plantation. Branches of Petite Anse bayou run along the northern and southern sides of the island and finally lose themselves in the marsh. Comnitinication with the main land. — Communication between Petite Anse and the main land was established earh^ in the pres- ent century by the building, from the northernmost point of the island, of a raised dirt way or causeway through the swamp.* Communication with the outer world by water was greatly hin- dered by the bar at the mouth of Petite Anse bayou. This was partially overcome in 1880 bj- the digging of a canal from the lower part of the bayou across the marshes to the Gulf. In 1886 a branch of the Southern Pacific was completed 'from New Iberia to the island. Topography Shape and area. — Calculations from the land office maps give the area of Petite Anse as 1,640 acres or about 300 acres less than Grande Cote. The island is somewhat oval, longest along its northwest and southeast diameter and has a marked indentation in the southwestern part. (See Plate 19.) Its greatest length is two and three-eighths miles and the narrowest place is barely a mile and a half. The hills. — The general relief of the island is well shown by the topographical map (Plate 31) and the model of the island (Plate 19). From them it will be seen that, while the island has no main central line of hills from which everything slopes, there is a principal hill cluster with minor ones about it. The main hill cluster extends from southeast to northwest, beginning with Plum hill, the second highest on the island, and extending to *The Emigrant's Guide to the Western and Southwestern States of Louisiana, Mississippi, Tennessee, Kentucky, Ohio, etc. by William Darby, with map. New York, 1818, p. 68. ni] The Five Islands : Petite Anse 239 Prospect hill and Round Top, which occupy separate spurs on the northern end. This dividing ridge does not fall below 80 feet and in the case of Prospect hill reaches a height of 152 feet. Its eastern slope contains two deep pit-like depressions which are occupied by wooded ponds. A third upland lake or pond, Willow pond, separates Round Top from Smith's hill. From Smith's hill a chain of hills follow the shore line southwest to the beautiful residence of the Avery family where it turns and extends a little way southeast. A fourth pond valley, now almost entirely drained, separates Plum hill from Cherry hill which with its outliers occupies the southernmost point of the island. The whole group assumes on the map the appearance of a great, rude capital E near the middle of which is Salt mine valley. The lakes. — The three upland lakes are essentially the same as those seen on Grand Cote. Willow pond is reported to be 15 feet deep and is the principal ' ' crater of elevation ' ' of Thomassy. Wooded pond and De Vance's pond show remarkably well the rounded sink-hole shape of these valleys. The water level in the lake is between 35 and 40 feet above that of the Gulf. This would show the lakes to be of comparatively recent origin for the streams have not yet, even with this gradient, succeeded in cutting down their outlets. Near the old mine are numerous great funnel shaped open- ings whose origin has been fully explained in the discussion of the origin of the lakes on Grande C6te. Their depth ranges from 20 to 60 feet below the surface. To prevent water from running into these holes and thus into the mine a ditch has been dug to conduct the waters of the stream, which flows north of the office, into Willow pond branch. It originally emptied into Iron Mine run. History of Mining Operations Early period: Prior to 1862. — The existence of brine springs and possibly rock salt on Petite Anse was known to the aborigi- nal inhabitants of this country long before it was known to white man. A great deposit of potshreds and ashes in places three feet thick and extending over an area of possibly five acres 240 Geological Survey of Louisiana [Sect. testify to the extent of salt operations here in prehistoric times. The occurrence of a piece of basket work lying directly on the salt has given rise to the supposition that the existence of rock- salt was also know to the Indians. The springs were rediscovered in 1791 by John Hayes while hunting. In that day of slow transportation salt was not so readily obtained as now and an attempt was soon made to use the waters of these springs for making salt. This was three years after the first attempt was made to make salt from the brine springs of New York.* At the time of William Darby's visit (about 18 17) the springs had been in active operation for a number of years and had supplied, to a large extent, the demands of the settlements of Attakapas and Opelougas.f This activity was due to the demand and increased value of salt caused by the war of 1812. The operations were conducted by John C. Marsh then owner of the island. War period: 1862-186J. — Following the opening of the Civil war, salt became very scarce and John Marsh Avery, the 18 year old son of Judge D. D. Avery, built up the old salt works established by his grandfather John C. Marsh in 18 12. The demand soon overtaxed the capacity of the springs and Mr. Avery directed his negroes to clean and deepen the salt wells. The negro engaged in work on one of the wells when he had reached a depth of 16 feet cried up to " Massa John " that he had struck a hard log. Mr. Avery descended into the well and found the log to be a bed of rock salt. To Mr. Avery therefore belongs the honor of being the first to discover an important rock salt deposit in North America, and, considering the size and magnitude of the deposit, this is no small honor. This discovery. May 6, 1862, had been partially foreseen by Thomassy. In i860, in speaking of the brine springs on Petite Anse he states that they are formed by the dissolution of rock salt by rain water. At the time of Thomassy 's second visit the production was about 40 baskets of rock salt per * Mineral Resources of the United States for 1896. Non-metallic Products Except Coal. vSalt by E. W. Parker. i8th An. Rept. U. S. Geol. Sur. 1896-1897, Part V (con.) p. 1289. fThe Emigrants Guide etc. by Wni. Darby, New York 18 18 p. 68. X Geologic Pratique p. 78, i860. Geological Survey of Louisiana, Report, 1899 Plate j8 ' 15 16 17 18 19 20 2, 22 23 ShaH 25 26 27 28 "^ m ^ "^ LEGEND [Z] S E] sa E3 Sanil Sand and gravel Gravel Clay Sand and clay Lignit Gnvide Cdle Well Sections C.KOl.or.ICAL SURVKV OK LO.MSIANA, RK.-..UT, .S99 I'l.ATH 39 Contour Map of the Satt Deposit of (.'ramie lilrvulioii giirn in JWI bi/,no l.iilj Lc'cl J5V A. C. SATcn Geological Survky of Louisl^xa. Kktort, 1S99 Platk 30 joo 100 O N N 300 * * ^ss^S'^^^^*^ ^=^5^!^^ -c ■•J^,r^ ^^ ^4^ ^*^ T=S:^ . ^^^ ^ ^ ^^ >..^*L.-^- GULF - ■->-- ■ ■' ■ ''/" 'i-i-- --^^i • ■ tfi/fi. jfc *'- S A L t\> I V" '";••. A'' yT \ Ml. ■" ^ ♦ ■*" ^ + *2 Mi. 1 ■. y^ ->- ■^ ^- f Section C-D 306 Section E-F O'055 Section of Grande Cote Ill] The Five Islands : Petite Anse 241 day.* The salt was quarried from a number of large open pits. This was a scene of great activity until the destruction of the works b}^ the Federal forces under General Banks, April 17, 1863. f The amount of salt taken out is estimated between 10,000 and 30,000 tons. Present period : i86y-i8gp. — After this, little or no work was done in mining the salt till 1867 when Chouteau and Price sunk the first shaft 8x8 feet and 83 feet deep ; a depth which was afterwards increased to 90 feet. Of this, 58 feet were in solid salt. At the time of Hilgard's visit (Nov. 1867), galleries eight to ten feet high and 25 feet wide had been driven east and west to a distance of 150 feet each way. Work was finally abandoned by Mr. Chouteau in 1870 upon the death of Mr. Price. In 1879 the mines were leased to the Galveston company and in 1880 were transferred to the American Salt company. The American Salt company occupied Chouteau's 90 foot shaft and fitted up a mill at the mouth of the shaft for crushing the salt. In order to secure transportation, a canal was cut across the marshes from near the mouth of Petite Anse baj^ou to the Gulf, *Supplement a la Geologic Pratique de la Louisiane. He Petite Anse. Bull. Geol. Soc. France, 2d series, vol. 20, 1863, p. 543 f This date of occupation is taken from extracts of the New Orleans Era of April 19, 1863 published in the New York Times April 27. This is quite interesting as giving a very early newspaper discription of the island and as showing something of the extent of the mining operations at that time. " For the last two months it" (the Steamer Cornie) "has been constantly employed in carrying salt from the mines, seven miles southwest of New Iberia, to the junction of the Teche and Cahawba Bayous. From this point the salt has been transported to Alexandria, and by way of Red River, to Vicksburg, Port Hudson and other places occupied by the rebels." * * * * * " Seven miles west of New Iberia and near Vermillion bay, in the middle of a mud lake, thick grown with flag and cane, rises a ledge of solid rock, the surface and depth of which have not yet been discovered. From this mine thousands of dollars' worth of the best salt has been daily sent away for the use of the rebel army. Negroes were employed to blast and break it up, some being ground at the mine. It is reported that the rebels paid four and a half cents per pound for what they took away. When our troops reached Iberia" (April 17) "a regiment was sent to destroy all tools and machinery there. " See also Annual Cyclopaedia, 1863, Appleton and Co. New York p. 70, 1867. P 242 Geological Survey of Louisiana [Sect. A tramway was built from the mine and a short embankment made across the marsh to Petite Anse bayou where a number of slips were dug. The salt was loaded in lighters and carried down the bayou to Vermillion ba}^ where it was transferred to schoon- ers. This did not prove very satisfactory because of the cost of transfers and accidents to the lighters and 5chooners due to mud- flats and bars. The salt was mined bychambei's and cross-headings averaging about 40 feet wide and 25 or more feet high, pillars 40 feet in diameter being left to support the roof. In 1886 the American Salt company was succeeded by the New Iberia Salt company'- which made arrangements with the Southern Pacific railroad for a switch from New Iberia. This was completed in 1886 and solved the question of transportation. The extreme irregularity of the surface of the salt was not fully appreciated by the companies first engaged its mining. The surface of the salt changes in one case from 20 feet below the ground to loo feet in ja distance of less than 200 yards. The galleries on the 90 foot level were driven under the false idea that there was 40 or 50 feet of salt above them and soon approached the outer limit of the salt. Then water commenced to come in the mine through the crevices. After the water had started, it did not take long for it to dissolve the salt and change the crevices into holes. Thus the first sink-hole was formed as early as 1883. Others followed and the sand and water and debris carried into the mine through the sink-holes very greatly interfered with the mining operations. First the eastern and then the western side of the mine was abandoned and it was decided (1885) to sink the shaft 70 feet deeper. This additional depth, with the eight feet required for the pump, made the total depth of the working shaft 168 feet. Work was prosecuted on the 160 foot level by driving galleries and crossways 80 feet wide and 40 feet high and leaving supporting pillars 60 feet in diameter. July I, 1893, Myles and company of New Orleans, obtained a sublease of the property. The water which entered the upper levels through the sink-holes finally effected an entrance to the lower levels and caused that part of the mine to be abandoned in Ill] The Five Islands : Petite Anse 243 July, 1895. Operations were continued in the upper level till 1896 when the mines reverted to the Avery family by default of contract. Appreciating that the life of the present mine is limited, in 1898 a new company was formed under the name of the Avery Rock Salt Mining company, to carry on operations in the old mine and to sink a new shaft. Borings were made and a site was selected southwest of the old mine and beyond the limits of the old workings. After considerable trouble with water bearing sands and gravels, salt was entered at a depth of 54 feet. The shaft at the time of the writer's visit had reached a depth of 125 feet and some trouble was still being experienced from water coming in between the salt and the timbers of the shaft. Geology Surface Geology. — While showing commonly a brownish lowyel loamy soil, this island differs* from the others in the numerous surface exposures of gravel. The grayel and sand out- crops seem to be confined entirely to the southern extremity. Sand and gravel are particularly abundant to the southeast on Cherry hill and at the shaft. Some gravel is exposed in the sandpit on the railroad track and in the sandpit between the house and the store. The sand and gravel obtained from the pits is used quite extensively along the line of the Southern Pacific. While the bank sand is of fairly good quality the best is obtained near the mouths of the ravines where the water has washed out the little clay it contains. On the northern part of the island there are numerous outcrops of a variegated chocolate, yellow or green jointed clay. The notable ones are on the northwest slope of Prospect hill, on the western .slope of Smith's hill, in the cut north of Avery's station and on both the eastern and western slopes of Residence hill. On the eastern slope of Residence hill, Hilgard reports finding besides imperfect vegetable remains, shells of Paludina, several species of Unio and a Cyclas. The writer was unable to find any specimens which could be identified. The false bed- ding and cross-bedding of these strata render dip determinations practically impossible. 244 Geological Survey of LouIvSiana [Sect. Lignite. — One of the gullies at the head of Iron Mine Run hollow exposes part of a bed of lignite, 65 feet above tide. An attempt was made to mine this for local consumption but it was soon given up. A shaft 30 feet deep was sunk exposing the following section : No. 1 . Yellow clay 1 2 ft. 2. Lignite 18 ft. 3. Clay not passed through. Something of the thickness of this underclay is shown by a boring 85 feet deep made about 100 yards, a little north of west from the lignite shaft, which passed through nothing but clay. The lignite as exposed in an excavation in one side of the gully shows a dip of 44°, S. 69° E. If this is the dip shown in the mine the real thickness of the lignite is about 12 feet. This dip led Bolton to surmise that the lignite and sandstone, shown further down the same ravine, dipped beneath the salt. Section at deep boring. — That this idea is incorrect is shown quite conclusively by a deSp boring about 220 yards from the lignite in the direction of the shaft. Section of Deep Boring (Elevation 48 feet above tide) No. Depths 1. o- 4. Fine sandy clay soil 4 ft. 2. 4- 160. Very fine grained, soft pink and drab or purple sandstone 156 ft. 3. 160- 166. Hard, coarse grained, chocolate colored sandstone 6 ft. 4. 166-1005. White rock salt not passed through 839 ft. This section clearly shows the sandstone on top of the salt and indicates an unconformity between the salt and the overlying beds. A dip of slightly more than 44°, S. 69° E., would be quite sufficient to account for the absence of lignite in this section. The absence of gravel is quite con.spicuous. Sandstone of Iron Mine ru7t. — The sandstone, 3, of the above section, is exposed all along the sides of the ravine from the deep boring almost to the bridge near the shaft . As exposed it is a very fine grained pink sandstone with here and there pieces of specular iron ore. It is to these bits of iron that the in] The Five Islands: Petite Anse 245 branch owes its high sounding name. The sandstone outcrops along a line running northeastward in the direction of Willow pond but no fragments or outcrops were seen beyond this pond. It has been suggested that this stone might be used for railroad ballast and concrete work but no careful tests have yet been made. Section northeast of the mine. — The large sink hole northeast of the mine reaches a depth of 63 feet below the level of the top of the shaft. It thus affords an excellent exposure. It shows little besides white and orange sands with occasional gravel, and masses of clayey sand. On account of crossbedding, falsebed- ding and landslips, the stratiiication could not be satisfactorily determined. Vertebrate remains. — The most interesting sections to be seen are in the sink holes which occupy the region between the old and the new shafts. Here are the bone and potter}^ beds which have been cited as evidence that man and mastodon were cotem- poraneous. The first notice of vertebrate remains on the island, so far as we are aware, was given by Prof. Joseph Henry in a paper before the Chicago Academy of Sciences on the verbal statement of Mr. T. F. Cleu, who contributed a specimen of basket work to the Smithsonian Institution.* Owen mentions the occurrence of pottery, but says nothing about fossil vertebrates. In 1883 Mr. William Crooks, of the American Salt company, presented to the Smithsonian Institution a collection of bones obtained in sinking an air shaft. These were turned over to Prof. Joseph Leidy for examination. He made them the subject of a brief communica- tion to the Philadelphia Academy of Sciences in 1884 f and of a detailed report published in the Transactions of the Wagner Free Institute of Science in 1889. J In this he lists : Mastodon americanus. Mylodon harlani Owen. Mylodon sp. (cf. robiistus Owen). Equus major De Kay. * Trans. Chicago Acad. Sci., vol. i, part II. t (Notes on Fossil Bones from Petite Anse, L,ouisiana) by Joseph Leidy, Proc. Acad. Nat. Sci. Phila., vol. 36, p. 22, 1884. X Notice of Some Mammalian Remains from the Salt Mines of Petite Anse, Louisiana. Trans. Wagner Free Inst. Sci., vol. 2, pp. 33-40, 1889. 246 Geological Survey of Louisiana [Sect. Late in the "eighties" General Dudley A. Avery sent sev- eral other bones to the Smithsonian Institution ; one of which was identified as the claw of a Megalonyx. Probably the largest collection which has 3et been made at this locality was by Dr. Joseph F. Joor, of New Orleans, for Tulane University, in 1890.* These were submitted to Prof. E. D. Cope. In his report he figures and describes two new species of Mylodon and considers that the teeth identified by Leidy as Eqiius majorJ)e.K.3.y really represent a new speciesf. The species determened by him are : Mastodon sp. Mylodon sulcidens Cope. Mvlodon harlanii Owen. Equtis intermedhis Cope- Mylodon renide^is Cope. To this list Dr. Joor adds doubtfully the remains of a.\\Elephas. The bone bed is a fairly rich one and may be expected to yield some good material to the careful worker. The section shown on the north side of the sink hole near the old air-shaft is : Section Near Air Shaft 1. Gray sandy loam with numerous pebbles 7 ft. o in. 2. Broken pottery and ashes i ft. o in. 3. Dark gray silt ; looks like hill-wash 5 ft. 6 in. 4. Finely laminated black loam containing many grass roots i ft. 6 in. 5. Medium coarse white sand grading above into gravel about the size of a pigeon's egg 2 ft. 5 in. 6. Black or dark brown, very hard, gravelly sand containing fragments of vegetable matter and Mastodon Mylodon and Equus bones. Exposed surface shows greenish yellow with sulphur efflorescence 2 ft. o in. 7. Salt. Exposed 10 ft. o in. On the south side of the same hole layer 6 becomes much thicker and grades into a dark tenacious clay. * Notes on a Collection of Archeological and Geological Specimens, etc. Am. Nat., vol. 29, pp. 394-398- f On Some Pleistocene Mammalia from Petite Anse, Louisiana, by E. D. Cope, Am. Phil. Soc. Proc, vol. 34, pp. 458-468, 3 plates, 1895. in] The Five Islands : Petite Anse 247 Leidy remarks tliat none of the bones examined by him showed any trace of erosion ; a statement which is confirmed by all the specimens collected by the writer. Just south of the new shaft in grading for the railroad embankment what appears to have been a fairly complete skeleton of a mastodon was unearthed and before it was seen by any one who realized its value it was buried in the embankment. A few bones which had rolled down to the foot of the embankment were picked up by General Avery and led to the disclosure of the above facts. About three feet of a tusk was afterwards found by one of the workmen in the side of the embankment. A few stray bones have been found in Iron mine run above the bridge. These are the only two localities where bones have been found outside of the lowest part of Salt mine valley. A^ew shaft section. — ^Just west of the last section the new shaft shows very little in common with the bone-bed section. Section at New Shaft I . Surface soil 4 ft. Yellow sand 12 ft. Sand clay and gravel. Water line 8 ft. Sand and gravel 30 ft. Salt ; The salt. — The salt is white, hard, dry, crystalline, commonly composed of many small crystsls from an eighth to a quarter of inch in diameter which are very irregular because of interference. Occasionally masses are found which are composed of very large crystals as shown on Plate 23. The salt here shows nothing of the upper dirty salt found on Belle Isle but is quite white so far as penetrated, with the exception of parallel bands of dark salt from two to six inches thick. These are best shown on a freshlj- blasted face. Analysis of this black salt by Mr. McCalla, at one time resident engineer and chemist, shows that the black bands contain seven per cent of insoluble matter, chiefly gypsum. Access could be had to only a very small portion of the mine, at the time of the writer's visit but Mr. John Averj^ Assistant Superintendent, states that the extravagant dip shown on the present working face is the same both in intensity and direction 248 Geological Survey of Louisiana [Sect. throughout the mine. The dip shown there is southeast. That is, if these really represent, as they seem to, lines of stratifica- tion, the salt is almost vertical. Pomeroy states however that a close examination reveals the fact that the salt is folded, the upper level showing three distinct anticlines. Analyses of the salt. — The remarkable purity of the salt and the absence of the usual impurities found in other rock salt deposits has been the subject of quite a good deal of comment and is one of the hardest points to meet in a rational explanation of its origin. Quite a number of analyses have been made, of which the following are the most important. Analysis of Salt Chemist. Jules Lafort 11—1863.. •• E. W. Hilgard*f— 1863 Peter Collier f Dr. Riddle f C. A. Goessman f C. A. Goessman i; i; Joseph Jones f . . . . .' F. W. Taylor 1882*+ .. Dr. Doremus f Gustavus Bode f Sodiujn Calcium chloride, sulphate. 97. 99- .920 880 .900 .880 .880 .88 ,617 71 .097 .252 .126 .838 .76. •79 .782 .318 1. 192 ■7293 .694 Calcium chloride. Mag- nesium chloride. Mag- nesium sulphate. other matter. Not deter- mined. 2.08 t. .146 .022 .080 .014 •13 ■23 1 t. t. •33 .400 .003 .062 •33 .003 t. ■013 ■1584 .030 .0389 .042 .012 Yearly production yearly production of output reached its railroad connections Kansas in i888-i88c of salt. — From the following table of the salt at Petite Anse it will be seen that the maximum shortly after the completion of and that after the discovery of rock-salt in ) it suffered a heavy decline. Although the The Petite Anse Salt Mine, by Richard A. Potneroy. Trans. Am. Inst. Min. Eng. , vol. 17, pp. 107-113, 1888. II Supplement 4 la Geologie Pratique. He Petite Anse. Comp. Ren. Gtol. Soc. France, 2d series, vol. 20, 1863, p. 543. * Mineral Resources of the United States for 1882, Salines of Louisiana, by E.W.Hilgard. p. 564, 18S3. •t- Mineral Resources of the United States for 1883-1884, p. 841, 1885. * Salt by C. .A. Goessman, Johnson's Universal Cyclopedia, New York, 1S95, vol.7, P-274. S American Cyclopjcdia. Salt. New York, 1881. vol. 14, p. 572 Buck, C. E., and Goes.sman, C. A. On the rock-.salt deposits of the Petite' Anse, La. Salt Company, Report of American Bureau of Mines, New York, 1867. ieOLOGlCAh SURVBV OF LOUISIANA, REPORT, 1899 Vofii>xm/ ^;7>a^ condition, is Kaolins 10- 25 lbs. per sq. in. Brick clays 60- 75 ' ' Pottery clays 100-150 " Paving brick clays 75-150 " Fire shri?ikage. — If after a clay has been air dried it is put in a furnace or kiln and subjected to a slowly rising temperature, it begins to shrink more, beginning at a low temperature and continuing upwards. This second shrinkage is known as the fire shrinkage and may be just as variable as the air shrinkage. It is due partly to the loss of chemically combined water which the clay contains, and also to the presence of other volatile materials such as organic matter in the clay. It is just as important that the fire shrinkage should proceed slowly in order to prevent cracking and warping of the ware. Fine grained clays usually shrink more in burning than coarse, sandy ones, and it is on this account that sand is sometimes added to the clay in the process of mixing and molding. Effect of heat on clay. — In addition to the fire shrinkage which has just been mentioned, there are certain other changes which take place during the burning of a clay and these depend on the temperature and also on the clay, whether pure or impure. If the clay is heated to a certain point, which will be the higher, the purer the clay, a softening of the particles takes place, or fusion begins. If the clay is not heated further than this point, it will on cooling be of a hard, rock-like natvire. but will still be porous. This is known as the condition of incipient fusion. A further heating to a temperature of from 75 to 200 degrees Fahr. Ill] Special Report No. 4 : Clays 269 causes the particles to soften still more under the action of the heat, so that they pack together in a smaller space, leaving no interstices. At this point the maximum shrinkage of the clay has been reached and the mass will also be impervious or very nearly so. It is what is known as the condition of vitrification. This is the state to which stoneware, paving brick and sewer pipe should be burned. But all clays do not yield the best results if burned to this point. If the clay is heated still higher it begins to soften still more and at a certain point becomes viscous or flows. This is there- fore spoken of as the point of viscosity. In clays which are to be burned to the condition of vitrification the points of vitrifica- tion and viscosity should be at least 150 degrees Fahr. apart and preferably 200 degrees. In limy clays the points of incipient fusion and viscositj' are very close together and consequently it is not possible to burn a kiln full of ware to vitrification without danger of running it beyond to the point of viscosity. In some fireclays the differcence between the points of incipient fusion and viscosity ma}' be as much as 600 degrees Fahr. In very impure clays incipient fusion may begin at as low a temperature as 1,700 degrees Fahr., while in fireclays this same point may not be attained below 2,700 degrees, and indeed it really should not in order to permit calling the clay refractory. Another effect of heating is the change of color that is brought about, especially by iron, for this is the great coloring agent of clay in both the burned and unburned condition. With a given percentage of iron, the clay when lightly burned will be light red, but as the temperature of the firing increases the color deepens, passing into deep red and finally, when the clay fuses, into bluish black. Again, the greater the quantity' of iron oxide in a clay the deeper will be the color produced at any given temperature. This production of the red color assumes that the condition of the kiln fires is oxydizing, that is that there is a supply of air. If there is an insufficient supply of the latter the the fire will act reducing and the color of the burned cla}' will be bluish instead of red. There are certain ingredients which tend to destroy the red- dening power of iron, and these are lime and alumina. It has 270 Geological Survey of Louisiana [Sect. been found that if the clay contains a large percentage of alumina, that the coloration produced by the iron will be much fainter than if the percentage of alumina were smaller. L,ime, however, is far more powerful in this respect than alumina, for if the lime percentage is only one and one-half times greater than that of the iron it begins to exert a bleaching action on the color of the clay in burning, and if the ratio of lime to iron is as three to one the brick instead of burning red will burn buff. This explains the cream color of many cream colored bricks. It should be added, however, that a small percentage of iron in a clay will produce the same shade, but the limy clay will not stand much heat whereas the one low in iron will, and further- more if they are overburned, the limy one will turn green- ish yellow, and the other will tend to pass into a deep buff or deep red. An important question with clay workers is the regulation of the temperature, and the production of similar results during a number of successive burnings. It, therefore, becomes neces- sary to have some means of judging the temperature of the kiln. One method consists in using a testpiece of clay, which shows certain effects when the burning has reached the proper point. Another method, which is a modification of the one just men- tioned, is to use what are known as Segers cones. These are little pyramid pieces of clays with other substances of a fluxing nature added. They are so compounded that there shall be a con- stant difference between their fusing points. These cones are numbered from .022 to 33. The theory of these pyramids or cones is that the cone bends over as the temperature approaches its fusing point, and when this is reached the tip touches the base. In actual use they are placed in the kiln at a point where they can be watched through a peephole, but at the same time will not receive the direct touch of the flame from the fuel, and it is always well to put two or more in the kiln so thas warning can be had of the approach of the desired temperature, as well as of the rapidity with which the temperature is rising. In order to determine the temperature of the kiln several cones are put in, as for example, Nos. .07, i and 5. Suppose Ill] Special Report No. 4 : Clays 271 that .07 is bent over in burning but 5 is not affected. Then the temperature of the kiln was between 3 and 5. The naxt time 2, 3 and 4 are put in, and 2 and 3 may be fused but 4 remain unaffected, indicating that the temperature reached the fusing point of three. If this is the temperature at which the burning of the kiln is completed then in future burnings it is only neces- sary to put cone three in the kiln and raise the fire until this bends over. These cones can be obtained for the sum of one cent each from Prof. E. Orton, Jr., of Columbus, O. In the testing of the samples of the lyouisiana clays these cones were used, and the fusibility of the clay is expressed in terms of them. For the temperature of the fusing points of these cones reference can be made to the following list which gives the fusion points in degrees Fahrenheit. Number of Fusing point Number of Fusing point Number of Fusing point cone degr's Fahr. cone degrees Fahr. cone degrees Fahr. .022 1094 .02 2030 18 2714 .021 1 148 .01 2066 19 2750 •020 1202 I 2102 20 2786 .019 1256 2 2138 21 2822 .018 1310 3 2174 22 2858 .017 1364 4 2210 23 2894 .016 1418 5 2246 24 2930 .015 1472 6 2282 25 2966 .014 1526 7 2318 26 3002 .013 1580 8 2354 27 3038 .012 1634 9 2390 28 3074 .Oil 1688 10 2426 29 31IO .010 1742 II 2462 30 3146 .09 1778 12 2498 31 3182 .08 1814 13 2534 32 3218 .07 1850 14 2570 33 3254 .06 1886 15 2606 34 3290 .05 1922 16 2642 35 3226 .04 1958 17 2678 36 3362 .03 1994 Slaking. — When a lump, or mass of clay is thrown into water it falls to pieces. This is called slaking. Some claj^s slake very rapidly, while in the case of others it proceeds so slowly as to be almost imperceptible. Sandy clays tend to slake more rapidly, than fine grained or dense ones, and shales will at times not slake at all, although on grinding and mixing with water they 272 Geological Survey of Louisiana Sect. show the same degree of plasticity as clay, for a shale is nothing more than a clay which has become consolidated by simple pres- sure of the overlying sediments that cover it. The practical bearing of slaking is twofold. It comes into play when the clay is being mixed with water before molding, when it is desired that the clay shall permit the tempering water to enter all of its pores both thoroughly and quickly. It also comes into play when clays are being washed in order to free them from any coarse particles of sand that they may contain, in which case if the clay slakes rapidly, the operation of washing can be carried on with greater speed and at the same time the result will be more complete. Physical Tests of Louisiana Samples 148. (Survey Xo. S3-) Alluvial clay R. R. track just S. of Little R. This was a somewhat gritty clay, and slaked easily when thrown into water. On working it up it developed very good plasticity, and required only 20 per cent, of water to mix it, which is low. The tensile strength of air dried briquettes made from this mass is 55 lbs. The ratio of fine to coarse particles is shown b}- the mechani- cal analysis which gave Clay and fine silt 73 per cent. Fine sand 27 The bricklets made from the clay had an air shrinkage of 6 per cent. At cone 3 the total shrinkage was 75^ per cent., and incipient fusion had begun. At this temperature the clay burned to a good red color. It contains small specks of p^^rite which pro- duce little fused spots when the clay is burned. At cone 5 the shrinkage is the same and vitrifaction began at 9. The clay is not to be classed as a fire cla}' for it is thoroughly viscous at cone 26. It would no doubt work for the manufacture of a good grade of brick, and would perhaps lend itself to the molding of pressed brick by the dry-press process. 149. (Survey No. 40.) This is also coarse, grained sandy clay and at the same time one that slakes very rapidly. Ill] Special Report No. 4 : Clays 273 It took 21 per cent, of water to work it up and the air shrink- age of the bricklets made from this mass was 10 per cent. The mechanical composition is verj^ similar to the preceding one and is : Clay and fine silt 73-50 per cent Very fine sand 26.30 ' ' 99.80 The tensile strength was 45 lbs. per sq. in. which is sufficient for a brick clay, but really should be greater. At cone 3 the claj^ burns light red and shows signs of incipient fusion. At cone 5 the total shrinkage was 13 per cent, and the color of the bricklet had changed to a deep red, while the iron oxide mixed in with the clay substance had caused the latter to sinter, but the brick was by no means vitrified. In burning it would be best not to raise the temperature above cone 3, for it destroys the color and also the texture of the body. The clay contained but a trace of soluble salts and therefore there would be but little danger of its becoming covered with a coating unless it were from the mortar after being set in the wall. 150. (Survey No. 62.) Carter's potterj- works, 2^ mi. E. of Robeline, La. This is quite a plastic clay and one of the best of the lot sub- mitted. As the tensile strength often stands in more or less direct relation to the plasticity, it may be remarked that the latter is 75 lbs. per sq. in. The mechanical analysis also indicates that the clay has mostly plastic particles, for it gave Fine sand None Fine silt 80.75 per cent Clay 20. 20 ' ' 100.95 At cone i the clay burns hard and dense with a total shrink- age of 13 per cent. At cone 3 the shrinkage was the same, but vitrification had begun. At cone 5 the clay began to get viscous. This would bar it out from being a fireclay. It burns however R 274 Geologicai< Survey of Louisiana [Sect. to a ver}' dense hard body, and could perhaps be used for paving brick. The percentage of soluble salts amounted to a mere trace. It would work for common earthenware articles of small size, but for stoneware it would probably be found more desirable to mix it with a more plastic cla3\ 151. (Survey 10.) Sec. 17, T. 3 N., R. 11 W. This clay is very plastic and while it contains little coarse grit it has much very fine sand. It took 31 per cent of water to work it up, and the tensile strength of the air dried briquettes was 75 lbs. per sq. in. The mechanical analysis gave : Cla}^ and fine silt 42. 10 per cent Very fine sand 57-25 " 99-35 The air shrinkage was 1 1 per cent. At cone 3 the clay burned light red and the total shrinkage was 12 per cent. At cone 6 the total shrinkage was 14 per cent and the color of the brick brownish red, while incipient fusion had begun. If burned to this temperature the clay would no doubt make a good grade of face brick. It is not a fire clay for at cone 26 it became thoroughly viscous. The clay contained but one-tenth per cent, of soluble salts. Like the preceding it would do for making earthenware, and good pressed brick as well. 152. St. Joe Brick Clay, St. Tammany Parish, La. A sandy mottled clay that slakes very fast. It took 21 per cent of water to work it up and gave a plastic but slightly gritty mass, which for practical purposes does no harm. The tensile strength of the air dried briquette was 60 lbs. per sq. in. The mechanical analysis 5'ielded, Fine sand 63.00 per cent Clay and fine silt 36.50 " 9950 The air shrinkage was only 4 per cent which is due to the high sand percentage shown by the mechanical analysis. At cone 3 the clay burns bright brick red and shows specks of fused pyrite. Ill] Special Report No. 4 : Clays 275 At cone 5 the color was still red and the shrinkage was 8 per cent, while incipient fusion had begun. At cone 26 the clay was completely vitrified. It is to be regarded as a semi-refractory clay, bnt not good for fire-brick. There was onl}' a trace of soluble salts. 153. Sec. 17, T. 3 N., R. II W. This is a soft gritty shale with flakes of mica and much organic matter. It took 35 per cent, of water to work it up but did not give a very plastic mass. The air dried briquettes had a tensile strength of only 30 lbs. per sq. in. The air shrinkage amounted to 9)^ per cent. At cone i incipient fusion occurred and the color of the brick was red. The total shrinkage up to this point was 12 percent. At cone 5 vitrification began and the shrinkage was 13 percent. The soluble salts amounted to three-tenths of one per cent, which is not excessive, but enough to yield a coating. While the clay burns dense at a comparatively low tempera- ture, viz., cone 5, at the same time it lacks in plasticity, and if it is desired to use it for paving brick or stoneware it should be mixed with a more plastic clay. In conclusion it may be said that all of the clays submitted would, when used alone work for pressed brick, one for paving brick and two for earthenware. Attention should be called to the fact that the points of incip- ient fusion of all lie somewhat higher than they do in most brick clays, and therefore the best results will be obtained by burning them in permanent walled kilns. There is a great tendency among Southern brickmakers to not only underburn their bricks, but also to mix sand with the clay, when there is already enough sand in it. special Report No. 5 A REPORT ON A COLLECTION OF FOSSIL PLANTS FROM NORTHWESTERN LOUISIANA BY Arthur Hollick CONTENTS Letter of Tratismittal Cryptogamia Pteridophyta POLYPODIA CE.E Pteris pseudopennaeformis, 279 Phanerogamia ANGIOSPERM.5i-MONOCOTYI.EDON.C GRAMINE.E Poacites sp., 279 CYPERACE.K Cyperites sp. 279 ANGIOSPERM.*;-DlCOTYI,EDON.5i JUGLANDACE.E Juglans rugosa, 280 Juglans schimperi, 280 FAG ACE. E Quercus microdentata, 280 iL..yACE.E Ultnus tenuinervis, 280 MORACE.]-: Artocarpus dubia, 281 Artocarpus lessigiana, 281 Artocarpus pungens, 281 Ficus artocarpoides, ? 281 Ficus harrisiana, 281 Ficus planicostata, 282 Toxylon longipetiolatum, 282 Ill] Special Report No. 5 : Fossil Plants 277 MAGNOLIACE.^. Mag-nolia hilgardiana, 282 Magnolia lanceolata, 282 LAURACE.K Cinnamotnutn buchi, 283 Cinnamomutn scheuchzeri, ? 283 Cinnamomum sezannense, 283 Cryptocarya eolignitica, 283 Daphnogene kanii, ? 284 Laurus primigenia, 284 Persea speciosa, 284 Tetranthera prsecursoria, 284 AQUIFOLIACE.E Ilex? affinis, ? 285 Ilex sp., 285 CELASTRACE.E Celastrus taurinensis, ? 285 Celastrus veatchi, 285 SA PIN DACE. K Sapindus angustifolius, 286 RHAMNACE.E Rhamnus cleburni, 286 CORNACE.E Cornus studeri, ? 286 ERICA CE.E Andromeda delicatula, 287 Andromeda eolignitica, 287 SAPOTACE.E Sapotacites americanus, 287 OLEACE.E Fraxinus johnstrupi, ? 287 APOCYNACE.E Apocynophyllum sapindifolium, 288 A REPORT ON A COLLECTION OF FOSSIL PLANTS FROM NORTHWESTERN LOUISIANA LETTER OF TRANSMITTAL Columbia University, New York, N. Y. Sept. 23, 1899. Professor G. D. Harris, Cornell Uuiversity, Ithaca, N. Y.: Dear Sir : I transmit with this a report upon the collection of fossil plants from the vicinity of Shreveport, La., which you sent to me for examination some months since. The collection numbers about 175 specimens, the majority of which are beauti- fully preserved. The larger number, and best specimens, are in a fine reddish sandstone *; a few are in gray sandstone t and the remainder in clay J or cla}" concretions || . About 50 species are represented. Of these I have been able to identify 30 either positively or provisionally. Six others I have described as new species. They are all dicotyledonous angiosperms, with the exception of two monocotyledons and one fern, and they indicate a Lower Tertiary horizon. Very truly yours, ARTHUR HOLLICK. * % mile above Coushatta, La. f K. C. P. & G. R. R. cut, I mile west of Shreveport, La. X Slaugliter-Pen bluff, Shreveport, La. II Vineyard bluff, Cross bayou (>^ m. above Slaughter-Pen bluff), Shreve- port, La. Cryptogamia Pteridophyta POL YPODIA CE^ Pteris pseudopennseformis, Plate 32, fig. i. Pteris pseudoperuiceforniis Lesq., Tert. Fl. p. 52, pi. 4, figs. 3, 4. Our specimen is the best one of this species thus far figured and gives a clear idea of the difference between it and P. penyi^F- formis Heer, Fl. Tert. Helvet., vol. i, p. 38, pi. i , fig. i, with which it was originally confused by Lesquereux. In addition to the fragments figured by lycsquereux another by Newberry ma^- be found in his Later Kxtinct Floras, etc., Monog. U. S. Geol. Surv., vol. 35, pi. 48, fig. 5. In hard clay concretions, A^ineyard bluff, Cross bayou (^ m. above Slaughter-Pen bluff), Shreveport, La. Phanerogamia Angiosperm^-Monocotyledon^ GRAMINE^ Poacites, sp. Plate 32, fig. 2. This is evident^ a portion of a leaf blade of some monocotyle- don, apparently a grass, and may be compared with similar fragments described under the genus Poacites, such as P. Icsvis Al.Br., depicted by Heer in Fl.Tert. Helvet., vol. i, pi. 25, fig. 10, P. finnus Heer, ibid., fig. 11, etc. In soft clay, Slaughter-Pen bluff, Shreveport, La. CYPERACE^ Cyperites, sp. Plate 32, figs. 3, 4. These specimens are evidently fragments of monocotyledons, which may be placed in the genus Cyperites for convenience, although they might equally well be considered as belonging to the Palms. In soft clay, Slaughter-Pen bluff, Shreveport, La. 28o Geological Survey of Louisiana [Sect. Angiosperm^<:-Dicotylkdon.«; JUGLANDACE.^ Juglans rugosa, Plate 35, figs, i, 2. J2igla7is rugosa Lesq., Am. Journ. Sci., vol. 45 (1868), p. 206 ; Ten. FL, p. 286, pi. 54, figs. 5, 14; pi. 55, figs. 1-9; pi. 56, figs. I, 2. In red sandstone, % m. above Coushatta, La, Juglans schimperi, Plates 32, fig. 5 ; 33, figs. 1,2; 35, fig. 3. Jiiglans sdiimperi Lesq., Ann. Rep. U. S. Geol. and Geog. Surv. Terr., 1871(1872), Suppl., p. 8 ; Tert. FL, p. 287, pL 56, fig. 5-10. Although these specimens vary considerably amongst them- selves they occur in such close proximit}^ in the rock that I havt thought it advisable to include them all under the one species. In regard to our fig. 2, pi. 33, there can be no doubt, when com- pared with Lesquereux' fig. 5, pi. 56, above quoted, buttheothers might be more or less successfully compared with/, dubia Ludw., Palaeontog., vol. 8, pi. 59, figs, i, 2, or with/, occidentalis Newb. , Later Ext. FL, Monog. U. S. Geol. Surv., vol. 35, pi. 65, fig. i ; pi. 66, figs. 1-4. In red sandstone, Y^^ m. above Coushatta, La. FAGACE.-E Quercus tnicrodentata, n. sp., Plate 34. Leaf elliptical in outline, about 8>^ in. long by 3>^ in. broad in the middle ; finely dentate-serrate from below the center to the apex, entire and wavy margined below ; secondary nervation fine, sub-parallel, leaving the midrib at an angle of about 45 degrees, curving upward near the margin, each nerve ending in one of the teeth, or the lower ones extending close to and upward along the margin. In red sandstone, % m. above Coushatta, La. ULMACE.-E Ultnus tenuinervis, Plate 32, fig. 6. Ulmus tenuinervis Lesq., Ann. Rept. U. S. Geol. and Geog. Surv. Terr., 1873, (1874), p. 412 ; Tert. FL, p. 188, pi. 26, figs. 1-3. In red sandstone, yi m. above Coushatta, La. Ill] Special Report No. 5 : Fossil Plants 281 HORACES Artocarpus dubia, «. sp., Plate 38, fig. 3. Leaf irregularly three-lobed, lower lobes short, obtuse, ascending, middle lobe broadest near the middle and tapering to a pointed apex, base wedge- shaped ; secondary nei^-ation pinnate throughout and camptodrome. It is possible that this may be merely a young or small leaf of A. lessigiana (L,esq.) Kn., but it appears to be so distinct and is so well defined that I have thought it best to describe it as a new species. In red sandstone, ^ m. above Coushatta, La. Artocarpus lessigiana, Plate 37. Artocarpus lessigiana (Lesq.) Kn., Science, vol. 21, (1893), p. 24 ; Myrica ? lessigiana Lesq., Ann. Rept. U. S. Geol. and Geog. Surv. Terr., 1874,(1876), p. 312; Myrica f lessigii Lesq., Tert. Fl., p. 136, pi. 64, fig. i. In hard clay concretions, Vineyard bluff, Cross bayou, (j^^ m. above Slaughter-Pen bluff) Shreveport, La. Artocarpus pungens, Plate 38, figs, i, 2. Aralia pimgens Lesq., Cret. and Tert. FL, p. 123, pi. 19, figs. 3, 4- In red sandstone, ^ m. above Coushatta, La. Ficus artocarpoides, ? Plate 35, fig. 4. Ficus artocarpoides Lesq., Cret. and Tert. Fl., p. 227, pi. 47, figs. 1-5- Our specimen is too imperfect for satisfactory identification and I have therefore only referred it provisionally to this species. It agrees very closely with Lesquereux, fig. 3, above quoted. In red sandstone, ^ m. above Coushatta, La. Ficus harrisiana, n. sfi., Plate 46, fig, 2. Leaf about 31^ in. long by 3>^ in. broad across the middle ; constricted to a blunt (?) apex and wedge-shaped at the base ; margin entire and wavy ; three-nerved from the base and with two pairs of prominent sub-opposite secondaries above ; midrib strongest, basal nerves branched from the lower side; all nervation finally thinning out and inosculating near the margin, tertiary nervation mainly at right angles to the primaries, secondaries, and sub-secondaries, but broken in places by finer cross reticulations. It is with hesitation that I have finally decided to place this leaf in the genus Ficiis. In some respects it suggests Aralia, and in others Hedera and in general appearance is not unlike 282 Geological Survey of Loulsiana [Sect. //. aiiriculata Heer, Fl. Foss. Arct., vol. 2., Fl. Foss. Alask., p. 36, pi. 9, fig. 6, but it i.s a much larger leaf and I have not been able to compare it satisfactorily with any described species in either genus. The specific name is given for Prof. G. D. Harris, through whose efforts the collection containing the specimen was brought to my attention. In clay concretions. Vineyard bluff, Cross bayou, {^/z mile above Slaughter-Pen bluff) Shreveport, La. Picus planicostata, Plate 36. Ficus planicostata Lesq., Ann. Rept. U. S. Geol. and Geog. Surv. Terr., 1872, (1873), p. 393; Tert. Fl., p. 201 pi. 31, figs. 1-8, 10-12. Our specimen is larger than any of those figured by I,es- quereux, but otherwise it agrees too closely with the species to warrant a separation. In soft clay, Slaughter-Pen bluff, Shreveport, La. Toxylon longipetiolatum, ;/. i/>. Plate 48. Leaf, exclusive of the petiole, about 554^ in. long, slightly inequilateral, broadest in the middle, rounded and curving in a bow to the base, some- what constricted to a short point at the apex ; margin entire ; petiole about 3 in. long, curved; midrib curved ; secondaries simple, sub-parallel, curv- ing upward and approaching each other near the margin, all but the lower two pairs alternately arranged. In red sandstone, % m. above Coushatta, La. MAGNOLIACE^ Magnolia hilgardiatia, Plate 39. Magyiolia hilgardiana Lesq., 2d Rept. Geol. Recon. Ark., p, 319, pi. 6, fig. I. In red sandstone, ^ m. above Coushatta, La. Magnolia lanceolata, Plate 40. Magnolia lanceolata Lesq., Mem. Mus. Comp. Zool., vol. 6, (1878), No. 2, p. 24, pi. 6, fig. 4. Our specimen appears to be merely a more robust one of this species. It is also comparable perhaps with M. longipetiolata Etts., as figured in Foss. Fl. Bilin, pi. 41, figs. 8, 9. In red sandstone, ]i m. above Coushatta, La. in] Special Report No. 5 : Fossil Plants 283 LAURACE.^.. Cinnatnomum buchi, Plate 43, fig. i. Cinnamomum buchi Heer, Fl. Tert. Helvet., vol. 2, p. 90, pi. 95, figs. 1-8. Our specimen appears undoubtedly to be a large one of this species although it also closely resembles the allied species C. polymorphum (Al. Br.) Heer, as figured in the above quoted work, on plates 93 and 94, and C. spedabile Heer, ibid., pi. 96. In red sandstone, yl m. above Coushatta, La. Cinnamomum scheuchzeri, (?) Plate 41, fig. 4. Cinnamomum schuchzeri Heer, Fl. Tert, Helvet., vol 2, p. 85, pi. 91, figs. 4-22; pi. 92, figs, i-iob ; pi. 93, figs. I, 5. The reference of this specimen to the above species is made provisional on account of its imperfect condition ; there is but little doubt, however, that it is correct. In soft clay, Slaughter-Pen bluff, Shreveport, L,a. Cinnamomum se^jannense, Plate 42, fig. 2. Cinnamomum sezannense Wat., PI. Foss. Bass. Paris, p. 175, pl. 50, fig. 2 ; C. dubiimi Wat., ibid., p. 176, pi. 50, fig. 4; Daphnogene pedunculata Wat., ibid., p. 178, pl. 50, figs. 6-10; D. kmgiqua Sap. and Mar., Essai Veg. Marnes Heers. Gelind., p. 48, pl. 4, fig. 7; D. sezanne?isis Sap., Fl. Foss. Sezanne., p. 369 [81], pl. 29 [8] fig. 5, etc. There is but little doubt that most, if not all the leaves described under the above names are referable to one species, to which our specimen belongs. In addition to the above refer- ences comparisons even more satisfactory may be made with figs. 5 and 6, pl. 6, Essai Veg. Marnes Heers. Gelind and with figs. , 2 and 5, pl. 9, Rev. Fl. Heers. Gelind., of Saporta and Marion. In hard clay concretions. Vineyard bluff. Cross bayou {}4 m. above Slaughter- Pen bluff) Shreveport, La. Cryptocarya eolignitica, n. sp., Plate 42, fig. i. Leaf about 6 in. long (including a petiole of about y^ in. in length), by about "2% in. maximum width, at the middle, oblong-ovate in outline, slightly inequilateral, entire and wavy margined, tapering to the apex, abruptly curved at the base and extending a short distance down the petiole ; sub-three-nerved by the lower pair of sub-opposite secondaries, which start from a point about Yz in. above the base and curve strongly 284 Geological Survey of Louisiana [vSect. upward ; upper secondaries irregularly disposed, curving upward and all finally thinning out close to the margin ; tertiary nervation fine, forming a series of loops between the margin and the outer sides of the lower secon- daries. This beautiful leaf appears to be entireh' distinct from any heretofore described. It almost certainly belongs in the Lau- racecz and after a number of comparisons with living species in the genera Phoebe, O^-eodaphne , Litscea, etc. I have decided to place it as given above. In red sandstone, % m. above Coushatta, La. Daphnogene kanii, (?) Plate 41, fig. 3. Daphnogene kanii YLq.^x , Fl. Foss. Arct., vol. :., p. 112, pi. 14, figs. 1-5 ; pi. 16, fig. I. If our specimen were in a better state of preservation it would probably not be necessary to question the reference to the above species, of which it seems to be a small form. I have thought it best to so refer it however, rather than to attempt a descrip- tion of a new species founded upon fragmentary material. In hard clay concretion, Vineyard bluff, Cross bayou (_^ m. above Slaughter-Pen bluff) Shreveport, La. I/aurus pritnigenia, Plate 41, figs, i, 2. Laurus primigenia Ung., Gen. et Sp. PI. Foss., p. 423. I have included our specimens under this protean species largely for the reason that they may be satisfactorily compared with figures of specimens referred by other authors to the same species, notably by Heer, in Fl. Foss. Arct., vol. 7, pi. 77, figs. 8-13, and pi 78, figs. i-ii. In red sandstone, %. m. above Coushatta, La. Persea speciosa, Plate 41, fig. 5. Persea speciosa Heer, Fl. Tert. Helvet., vol. 2, p. 81, pi. 90, figs. II, 12 ; pi. 100, fig. 18. In red sandstone, 3^ m. above Coushatta, La. Tetranthera praecursoria, Plate 44, figs. 3, 4. Tetranthera prcrcursoria Lesq., Cret. and Tert. FL, p. 228, pi. 48. fig- 2. In red sandstone, % m. above Coushatta, La. Ill] SPEcrA.L Repo rt No. 5 : Fossil Plants 285 AQUIFOLIACE.^. Ilex? affinisi?), Plate 44, fig. 2. //(?;trf a/^«z5 Lesq., Ann. Rept. U. S. Geol. and Geog. Surv. Terr., Suppl. 1871, (1872), p. 8; Tert,. Fl., p. 270, pi. 50, figs. 2, 3. Our specimen is too imperfect for accurate comparison, but it appears to be an Ilex and is sufficiently near to Lesquereux' species for at least provisional reference. In red sandstone, % m. above Coushatta, La. Ilex, sp., Plate 43, figs. 2, 3. The two fragments figured apparently represent a leaf related to the genus Ilex or perhaps to Celaslrus, but they are too indefi- nite either for satisfactory comparison or as a basis for the description of a new species. Figures more or less closely resembling ours may be seen under /. longifolia Heer., Fl. Foss. Arct., vol. i., pi. 48, figs. 3-6 and /. hibschi Engelh., Sitzb. Isis, Jahrg. 1891, pi. i, fig. 1. In soft clay. Slaughter-Pen bluff, Shreveport, La. CELASTRACE.E Celastrus taurinensis (?) Plate 46, fig. r. Celaslrns taurinensis Ward, T^'pes Laram. Fl., Bull. V . S. Geol. Surv. No. 37, p. 79, pi. 34, figs. 5, 6. This specimen is placed provisionalh' under the above name as it is too imperfect for accurate identification. That it belongs in the genus Celastrus there can be but little doubt as may be seen by comparison with the figures above quoted and also with the closely allied species, C. abiifoliiis Ward, ibid., p. 80, pi. 35, figs I, 2. and C. borealis Yi&ox , Fl. Foss. Arct., vol. 2, Fl. Foss. Alask., p. 37, pi. 10, fig. 4. In fineness of serration it more nearly resembles the latter two species while in its nervation it is more like the species to which it is provisionally referred, especially as indicated in fig. 5 above quoted. In red sandstone, % m. above Coushatta, La. Celastrus veatchi, n. sp,, Plate 43, figs. 4, 5. Leaf about 3 in. long by ifi in. broad in the middle, elliptical in outline, tapering about equally to base and apex, obtusely or crenately toothed or the lower portion merely wavy, with a blunt tip at the apex ; midrib strong 286 Geological Survey of Louisiana [Sect. and straight ; secondary nervation well defined, curving upward, becoming brochidodronie or sub-caniptodronie through the tertiary nervation, with fine nervilles extending to the teeth and margin. These leaves closely resembles those of Elceocarpus eiiropceiis Etts., Foss. Fl. Bilin, Part III., p. i6, pi. 43, figs. 6-10, but ours almost certainly belong in the genus Celastrus and I have thought it best to consider them as a distinct species. The name is given for Mr. A. C. Veatch, the collector. In red sandstone, ^ m. above Coushatta, La. SAPINBACE^ Sapindus angustifolius, Plate 35, fig. 5. Sapiiidus angustifolius Lesq. Ann. Rept. U. S. Geol. and Geog. Surv. Terr., 1873 (1874), p. 415 ; Tert. Fl., p. 265, pi. 49, figs. 2-7. This little leaf appears undoubtedly to belong to the above species, although it might almost equally' well be compared with the leaf figured as Quercus elcena Ung. by Lesquereux in Cret. and Tert. Fl. , pi. 28, fig. 11. Its identity with the genus Sapindus, however, is much closer than with Quercus. In gray sandstone, i ra. west of Shreveport, La. (K. C. P. & G. R. R. cut). RHAMNACE.E Rhamnus cleburni, Plate 47, fig. i. Rhamiius cieburni Lesq., Ann. Rept. U. S. Geol- and Geog. Surv., Terr., 1872, (1873), p. 381 : Tert. Fl.. p. 2S0, pi. 53, figs. 1-3. In red sandstone, ^ m. above Coushatta, La. CORN ACE. 'E Cornus studeri (?) Plate 45, fig. 2. Cor?ijis sticderi Heer, Fl. Tert. Helvet., vol. 3, p. 27, pi. 105, fig. 18-21, In referring our specimen provisionally to this species I have followed the example of Lesquereux, who also questioned the reference of his specimens to the species. There can be but little doubt, however, that ours is identical with the one figured by Lesquereux in Tert. Fl., pi. 42, fig. 5. In red sandstone, % "^- above Coushatta, La. ni] Special Report No. 5 : Fossil Plants 287 ERICACE.^. Andromeda delicatula, Plate 45, fig. i. Andromeda delicatula \^es<\. , Cret. and Tert. Fl., p. 175, pi. 34, figs. 10, II. Our leaf appears undoubtedly to belong to this species, although considerabh^ larger than either of those figured by Lesquereux. In red sandstone, % m. above Coushatta, La. Andromeda eolignitica, n. sp.. Plate 47, fig. 2. Leaf lanceolate in outline, entire, about 6 in. long by 1% in. wide at the middle, tapering gradually to the base and somewhat more abruptly to the apex, which is constricted and narrowed into a point ; midrib strong and conspicuous ; secondary nervation not visible. This leaf was probably of thick leathery texture, in which the finer nervation was hidden. In outline it closely resembles the leaves figured b}' Lesquereux as Fiats laiiceolata Heer, in Tert. Fl. pi. 28, fig. 1-5, and also some of those figured by Heer as Salix longa Al. Br., in Fl. Foss. Arct., vol. 3, Nachtr. Mioc. Fl. Gronl., pi. 4, figs. 7-10 ; but inasmuch as the secondary nerva- tion in ours is lacking, I have thought it best to give it a new name. In red sandstone, ^4 m. above Coushatta, La. SAPOTACE.E Sapotacites americanus, Plate 42, fig. 3. Sapoiaciies aiuericamis Lesq., in vSafford's Geol. Tenn., p. 428, pi. 7 [K], fig. 8. In red sandstone, yl m. above Coushatta, La. OLEACE.E. Fraxinus johnstrupi (?) Plate 44, fig. i. Fraxinus johnstrupi Yi^^x, Fl. Foss. Arct., vol. 7, p. 113. pi. 80, figs 1,2. In comparing this leaf with figures of described species I found it almost impossible to decide between the one above quoted and Querciis jiiglandina Heer, ibid., p. 89, pi. 71, fig. 19; 288 Geological Survey of Louisiana [Sect. pi. 74, figs. 4-7: pi. 76, fig. 12, and pi. 102, fig. 9a, especiallyin regard to fig. 7, pi. 74. It also has some resemblance to Ilex grandi/olia Lesq., Cret. and Tert. Fl., p, 187, pi. 38, fig. i, but Lesquereux' specimen is too fragmentary for accurate com- parison. In red sandstone, % m. above Coushatta, La APOCVNACE.'E. Apocynophyllum sapindifolium, n. s/>., Plate 46, fig. 3. Leaf lanceolate, entire, slightly inequilateral, narrowed and decurrent for a short distance at the base ; midrib strong ; secondaries thin and regular, leaving the midrib at an acute angle near the base, at a slightly more obtuse angle upward, running parallel to each other for a short distance, and approaching each other close to the margin, where they curve upward; tertiary nervation straight, sub-parallel and essentially at right angles to the secondaries. This leaf might be provisionally referred to several described species tinder the genera E'tc7is and Laurus, but some slight dif- ference in each instance has led me to think that it represents a new species. Interesting comparisons may however be made with Ficus lanccolata (Heer), Web., as figured by Lesquereux in Tert. FL, pi. 28, figs. 1-5 ; Laiitiis princepsY{&^x , by the same author, in Cret. and Tert. Fl. pi. 58, fig. 2 and L. primigenia Ung., as figured by Velenovsky in Tert. Fl. Laun, pi. 5, figs. 1-5. In red sandstone, yi m. above Coushatta, La. Note. — After page proof of this report had been set up my attention was called to a paper b}- Professor H. Engelhardt, entitled " L'eber Tertiarpflan- zen von Chile," (Abh, Senckenb. Naturf. Gesellsch. vol. 16 (1891), pp. 629-692. pis. I -14) in which are described and figured a number of species identical with ours but under different names. Of special interest is his Goeppertia spectabilis, which is undoubtedly identical with my Cryplocarya eolignitica, in which case Engelhardt's name has precedence. A H, GEOLOGiCAi, Survey ok Louisiana, Report, 1S99 6 Plate 32 I. Pteris pseudopenncsfortnis I^esq. 2. Poacites sp. 3, 4. Cyperites sp. 5. Juglans sckimperi I,esq. 6. Ulnius teniiinervis Lesq. Pp. 279-280 Geolo(;icai, Survey of Louisiana, Report, 1899 Plate 33 I, 2. fuglans schiniperi Lesq. P. 280 Geological Survey of Louisiana, Report, i8 Plate 34 Quercus microdentafa, n. sp. x %. P. 280 Geologicai- Si'KVEY OF LorisiA.vA. Kki'okt, 1899 I, 2. Juglans rugosa Lesq. P. 280. 3. Juglans schitnperi Lesq. P. 280. 4. Ficus ai'tocarpoides'L&?:i\.'^ P. 281. 5. Sapindus angustifolius'L.esq. P. 286. Geological Survey of Louisiana, Report, i8 Plate 36 Fiats planu'os/a/a hesq. P. 282. Geological Survey of Louisiana, Rei-ort, 1899 Plate 37 A rlocarfius /essigiana (hesq.) Kn. l"^^ nat. size. P. 281 Geological Survey of Louisiana. Report, 1S99 Plate ^8 I, 2. Aiiocarpus pungens{l.esi\). 3. Artocarpus dubia, n. sp. P. 281 Geological Survey of Louisiana, Report, 1899 Plate 39 Magnolia hilgardiana Lesq. P. 282 Geoi-ogicai, Survey of Louisiana, Report. i8 Plate 40 Magnolia lanceolatahsisq^., x ^. P. 282 Geologicai, Survey of Louisiana. Report, 1S99 Plate 41 1,2. Laurus primigenia Ung. 3. Daphnogene kanii l^^&x.l 4. Cin- namotHuni scheuchzeri Heer. ? 5. Persea speciosa Heer. Pp. 283-284. Geological Survey of Louisiana, Report, 1899 Plate 42 I. Cryptocarya eolignitica, n. sp. 2. Cinnanwmuni sezannense Wat. P. 283. 3 Sapotaates aniericanus Lesq. P. 287 Geological Survicv ok LofisiANA, Kkport, 1899 Pl.ATK 43 I. Clunamomwin buchi Yi^^r. P. 2S3. 2,3. Ilex sp. 4, 5. Celastrwi veatchi, n ?p. P. 285. Geological Survey of Lovisiana, Report, 1S99 Plate 44 I. Fraxinus johnsirupi Yi&&r.l P. 287. 2. /lex? qffinis hesq.? P. 285. 3, 4. Tetra7ithera pro'cursoria Lesq. P. 284. Geological Survky of Lgi'isia.va, Report, i8 Plate 45 I. Andromeda delicatula 'L^hq. P. 287. 2. Cornus s/ude/i Heer. ? P. 2S6 Geological Survey of Louisiana, Report, 1S99 Plate 46 I. Ce/asirt/s iaurinensis Ward. ? P. 285. 2. Ficus harrisiana, n. s^. P. 281. 3. Apocynophyllum sapindifoliuni, n. sp. P. 288 Geological Survey of Louisiana, Kki'ort, i6 Plate 47 I. Rhamnus cleburni Lesq. P. 286. 2. Andromeda eolignitica, n. sp. P. 287 Geological Survey of Louisiana, Report, li Plate 4S Toxylon longipetiolatutn , n. sp., 3^ nat. size. P. 282 Special Report No. 6 THE CRETACEOUS AND LOWER EOCENE FAUNAS OF LOUISIANA BY G. D. Harris CONTENTS Cretaceous Explanatory Remarks PELECYPODA Exogyra costata, 292 Gryphaea vesicularis, 292 Ostrea larva, 293 Ostrea plumosa, 293 Neithea quinquecostata, 294 Catnptonectes burlingtonensis, 294 I/imapelagica, 294 Cardium alabamense, 394 Inoceramus barabini ? 295 Veniella, sp., 295 Cras'satella vadosa, 295 Thetis, sp., 295 Trigonia eufaulensis, 295 I/inearea metastriata, 296 Iy is the name that will finally be applied to sinistral cephalopoda of this type. However, this is a very interesting specimen and deserves to be figured in this place. Locality .-Kz.yhwrvi' s salt works. Baculites anceps, Plate 51, fig. 6. Syn. — This species Stanton has regarded as anceps oi lyamarck, and probably regarded it as synonymous with B. asper Morton. Only small fragments have been so far found. They show the low undulations of asper as figured by Morton, though the suture line is not determinable. Z.^^Tdt/zV}'. -Ray burn's salt works. BRACHIOPODA Terebratulina sp., Plate 51, fig. 7. We have not seen any species figured that looks just like this. Whitfield's figures of Terebratella vanuxemi and T. plicata from N. J. have much coarser costae. The same is true of T. sayi Morton. Z.^ra/z/j'-.-Ray burn's salt works. KOCENE Midway Stage PELECYPODA Ostrea crenulitnarginata, Plate 52, figs. i. a. Syn. O. crenulimarginata Gabb, Jr. Acad. Nat. Sci., Phila., 2dser., vol. 4, p. 398, plate 68, figs. 40, 41, i860. 298 Geological Survey of L,ouisiana [Sect. For general synonymy and description, see Bull. Am. Pal., vol. I, p. 159, 1896. The state of preservation of this species in Lousiana is not the best. Specimens are firmly imbedded in the rock and fragments only can usually be obtained. In the bed of the brook however, there were a few loose, fairly well preserved specimens. It is these oyster shells that gave the rock in which they they are imbedded its limy character. Localit] — Raines' place, near Rocky Spring church, about six miles W. S. W. of Marthaville, Sabine Parish. The writer has personally collected this species also near the Cretaceous-Eocene border line in Texas, Arkansas, Tennessee, Mississippi, Alabama and Georgia. Ostrea pulaskensis, Plate 52, fig. 2, 3, 4. Syn. — O. pulaskensis Har., see Bull. Am. Pal., vol. i, p. 160. This is the Gryphce pitcheri Hilgard (Geol. Recon., Final Rept. 1869, p. 29) without doubt. Mr. Veatch found a large number of these 03'sters lying on some of the old dumps at King's salt works ; and it was probably here that Hilgard found his specimens. Vaughan has already called attention (Am. Geol., vol. 15, p. 297, 1895 and elsewhere) to the fact that " G. pitcheri is a Comanche series fossil and does not occur in the upper Creta- ceous," but he failed to state what the Louisiana specimens really should be called. Modiola stubbsi n. sp., Plate 52, figs. 5, 6. The general appearance and dimensions of this species are shown by the figures. It is specially characterized by the prominent angulation on the posterio-dorsal margin, and by the coarseness of the plications between this angulation and the most posterior point on the shell. The shell matter is thin and its various layers show a beautiful mother-of-pearl appearance, All specimens are broken and crumpled to a considerable extent. This species seems to have been the most common associate of the large oyster described above. Locality. — Raines' place, about six miles \\\ S. W. of Martha- ville. Ill] Special Report No. 6 : Lignitic Eocene Fauna 299 Turritella mortoni, Plate 52, fig. 9. Syn. — T. jnortoni Con., Acad. Nat. Sci., Phila., Jour. vol. 6, p. 221, pi. 10, fig. 2, 1830. See Bull. Am. Pal., vol. i, p. 224, ; vol. 3, p. 74. The fragments of this species are sufficiently well preserved to prove the existence of this species in association with the large oyster and the few other species found at the exposure given below. Locality. — Raines' place, near Rocky Spring church, about six miles W. S. W. of Marthaville. Fusus harrisi, Plate 52, fig. 7. Syn. — F- harrisi Aid., Bull. Am. Pal., vol. i, p. 64, pi. 5, figs. 2 and 8, 1895. See also vol. 3, p. 43, 1899. The only specimen we have of this species is by no means perfect as could be desired, but there seems to be no reasonable doubt regarding its identification. It has hitherto been known only from the lower L,ignitic at Gregg's landing and Yellow bluff on the Alabama river. Locality. — Raines' place, near Rocky Spring Church, about six miles W. S. W. of Marthaville. Iveiostoma ( ? ) ludoviciana, n. sp., Plate 52, fig. 8. We have a number of fragments of this Caricella- shaped species but none show its generic affinities beyond question. When broken oif anteriorly the shell has very much the shape and appearance of some varieties of Pseudoliva vetusta, but no trace of the characteristic furrow of that genus has been found. The anterior canal was shorter and more twisted than in Caricella. More material is needed for a satisfactory 'diagnosis of the species. It is here included on account of its strange appear- ance and association. Locality. — Raines' place, about six miles W. S. W. of Martha- ville, near Rocky Spring church, Sabine parish. LiGNITIC The fossiliferous localities of Sabinetown and Pendleton on the Texas side of the Sabine have already been described in this report, pp. 65-67. Though they are not on Louisiana soil, the 300 Geological Survey of Louisiana [Sect. horizons to which they belong are certainly to be found east of the Sabine, though generally not well exposed. Had these localities and their fossils been described in the Texas Survey reports or elsewhere a mere reference to them would have sufficed here. But since the Sabinetown fauna has long been misinterpreted and that at Pendleton has been unknown to previous writers, we have no hesitation in devoting some time to their study and space to their elucidation. PELECYPODA Ostrea thirsae, Plate 53, fig. i. Syn. — Gryphcsa thirsiB Gabb, Acad. Nat. Sci., Phila., Proc. 1861, P- 329- Ostrea thirs^z Heilp., U. S. Geol. Surv., 3d Annual, p. 311, pi. 63, figs. 4, 5, 6. O. thirscB Har., Bull. Amer. Pal., vol. 2, p. 40, pi. 12, figs. 5, 6. This species was originally described from Nanafalia, Ala., where it is found in great numbers. These specimens have in some instances the true thirsce appear- ance, but often they grade towards what we have believed to be the young of a variety of O. trigoyialis at Woods bluff. See pi. 12, Bull. Amer. Pal., vol. 2. Localities.— M2iX\?a2.\\\\^ R. R. cut: well, S. W. yi S. W. ]i S. 18, 7 N. ID \V. Horizoyi. — Lower Lignitic. Ostrea, sp. There are numerous fragments of large oj^sters found at Pen- dleton and elsewhere ; but so far we have not found sufficiently perfect specimens to warrant specific identification. Modiola alabamensis, Plate 53, fig. 2. Syn. — M. alabamensis Aid., Bull. Amer. Paleont., vol. i, p. 68, pi. 6, fig. 13, 1895. The specimens found are from Pendleton, Texas. It will doubtless be found in Sabine and other parishes of La., where the Lower Lignitic rocks crop out. Pinna sp. No special importance is attached to the finding of fragments Ill] Special Report No. 6 : Lignitic Fauna 301 of specimens of this genus in rocks from Cretaceous or Tertiary deposits. However, the silver}^, scaly character of the semi- disintegrated shell is rather noticeable and is apt to attract atten- tion and arouse wonderment as to the nature of the animal that produced it. It is a distant relative of the pearl oyster. Localities — La Nana ba^ou, near Many ; S. E. of Sodus, lime- stone concretions. Horizon — Lower Lignitic. Barbatia cuculloides, var. Plate 53, fig. 3. Syn. — Area cuculloides Q.o\\. , Foss. Shells, Tert. Form., p. 37, 1833. B. cuculloides Har., Bull. Amer. Pal., vol. 2, p. 239, pi. 14, fig. I, 1897. The members of this division of the Areas are somewhat vari- able in form and surface markings, and we have been unable to satisfactorily differentiate the Eocene species. In fact the Oli- gocene forms from Vicksburg, are perhaps of one and the same species with the Eocene. Localities.— ?^x\A\qX.ovl, Tex., S. W. }{, S. W. ]i, S. 18, 7 N., 10 W. Marthaville. Horizon. — Lower Lignitic. I/eda aldrichiana, var., Plate 53, fig. 5. Syn. — Yoldia aldrichiana Har., Bull. Amer. Pal., vol. 2. p. 245, pi. 14, fig. 15, June, 1897. Leda acala Dall. , Tr. Wag. Free Inst. Sci., vol. 3, 586, pi. 32, fig. 3, Oct. 1898. The Sabinetown specimens when compared with those from the type locality. Woods bluff, will be found to be somewhat broader posteriori}' or comparatively less ventricose anteriorly than those from the last mentioned locality. Yet the distance between the localities is doubtless sufiicent to account for a con- siderable amount of variation. It would certainly be unwise to propose a new specific name for these western specimens when the differences are confined to general outlines of the shells. Locality. — Sabinetown, Texas. Horizon. — Upper Lignitic. I/eda corpulentoides, var. Syn. — Yoldia corpulentoides Aid., Bull. Amer. Pal., vol. i, p. 70, pi 6, fig. 9, 9a, 1S95. 302 Geological Survey of Louisiana [Sect. See also Bull. Amer. Pal. vol. 2, p. 243. We must be in possession of better .«ipeciniens from the type locality before we can say just what L. corpulentoides is. See remarks on p. 343, vol. 2, Bull. Amer. Pal. It would seem, however, that this is a variety' of the species. Locality. — Pendleton, Texas. Horizon . — Lower Lignitic. Venericardia planicosta, Plate 53, fig. 6. Syn. — See Bull. Amer. Pal., vol. i. p. 172, vol. 2, p. 246. The specimens so far found in Louisiana are rather smaller than the average, but still are well formed. This is the most typical and important species of the Eocene series. Lignitic localities. — Sabinetown; i mi. E. of Ft. Jessup; Wms. farm; well, S. W. ^ S. W. ^ Sect. 18 7 N. 10 W.; La Nana ba5'ou. Astarte smithvillensis, Plate 53, fig. 7. Syn. — See Bull. Amer. Pal., vol. 2, p. 248. This .species seems to be very poorly represented in the Lignitic of Louisiana. Only one specimen, an exterior impression has thus far been found. It is from La Nana bayou near Many. See p. 69 of this report. Crassatella sp. Casts of what seem to be short, rugose Crassatellce have been found at several places, but they are too fragmentary for specific determination. They remind one of C. gabbi from the Midway of Tennessee. Localties. — Marthaville ; La Nana bayou. Kellia prima, Plate 53, fig. 11. Syn. — Kellia prima Aldrich, Bull. Amer. Paleont., vol. 2, p. 181, pi. 6, figs. 3, 3a. See also vol. 2, p. 202 and 250. We have already recorded this species from Sabinetown in the Bulletins of American Paleontology, p. 202 as given above. The specimens were in the Lea Memorial collection of the Phila- delphia Academy, and were collected by C. W. Johnson, of the Ill] Special Report No. 6 : Lignitic Fauna 303 Wagner Free Institute of Science. So far as known this species is confined to the Upper Lignitic or Woods bluff horizon. Cardium tuomeyi. Plate 53, fig, 9, 10. Syn. — C. tuojneyi A\d., Geol. Surv. Ala., Bull, i, p. 40, pi. 4, figs. 13, 13a, 1886. See also Bull. Am. Pal., vol. 2, p. 252. The specimens we have in hand are of the same species as those of the Lower Lignitic of Alabama. They often show, however, a somewhat coarser costation than the type specimen of tuomeyi does ; but so do many specimens from Nanafalia, the type locality. We have come to think the gap between toumeyi and hatchetigbeense not so very wide. C. hatchetigbeense is sup- posed to have fewer ribs and to have sharp large spines on the anterior and posterior slope. Many of these show this feature clearly. Locality. — Pendleton, Texas; Marthaville, La.; La Nana bayou, near Many, La. Horizon. — Lower Lignitic. Mactra bistriata, Plate 53, fig. 4. Syn. — M. prcstenuis var. bistriata Har., Bull. Amer. Pal., vol. 2, p. 258, pi. 19, fig. 10, 1897. With better specimens in hand it is safe to say that this is distinct from J/, prcstenuis, Con. Locality. — Sabinetown, Tex. Horizon. — Upper Lignitic. Corbula alabatnensis, var. Syn. — See Bull. Amer. Paleont., vol. 2, p. 260. Here is the same small varietal section of this species as noted in the above-mentioned Bulletin from various Lignitic localities in Alabama. It has no strongly marked characteristics by which to differentiate it from other members of this section. Locality. — Sabinetown, Tex. l/ucina ozarkana. Syn. — L. ozarkana Har., Bull. Amer. Pal., vol. 2, p. 264, 1897. These fragmentary specimens from Sabinetown seem to belong to the same species found in Woods bluff beds at Ozark, Ala. 304 Geological Survey of Louisiana [Sect, Ceronia. We cannot presume to identify or name specifically the frag- mentary specimens in hand. Suffice to say they seem to be quite common, and can easily be told by the silvery character of the shell matter. Locality. — Sabinetown and Pendleton, Tex. Pholas alatoideus, Plate 53, fig. 12. Syn. — See Bull. Amer, Pal,, vol. 2, p. 261, We have little doubt as to the specific identity of this imperfect cast with the Alabama Lignitic specimens. It will be observed, however, that in Alabama the species comes from the Lower Iviguitic, while this is from Sabinetown, and Upper Lignitic horizon. GASTROPODA Pleurototna huppertzi var. Syn. — P. huppertzi YQ.r pe7irosei Yi2ir . , Acad. Nat. Sci. Phila., 1895, p. 58, pi. 4, fig. 10. P. servatoidea Aid., Bull. Amer. Pal., vol. i, p. 59, pi. 5, fig- 5. 1895. The beds at Smithville, Texas, have a number of species with Lignitic affinities. This is very evident so far as the Pletirotoma are concerned. Th.& servatoidea diS, Aldrich has styled it in Alabama, is common to the Upper and Lower Lignitic, but so far as we are aware, has not yet been recorded from the Lower Claiborne. The specimen in hand is a typical Alabama Lignite form. Locality. — Sabinetown, Tex. Here in the Upper Lignitic. Pleurotoma silicata, Plate 54, fig. i, Syn. — P. silicata Aid., Bull. Amer. Pal., vol. i, p. 60, pi. 4, fig. 3, 1895. See also, vol. 3, p. 21, pi. 2,^fig. 13, 1899. There are quite a number of specimens of this species in our collection from Pendleton. In Alabama thus far the form is known only from Gregg's landing. This then goes to show, along with others, the close equivalence of these two localities on oppo- site sides of the Mississippi, so distant from each other. Locality. — Pendleton, Tex. Ill] Special Report No. 6 : Lignitic Fauna 305 Pleurotomella veatchi, n. sp., Plate 54, fig. 2. Specific characterization. — Size and form as figured ; spiral whorls about six ; somewhat angular centrally, especially the larger ones, crossed by twenty or more fairly well marked ribs with directions as follows : commencing just below a well-marked suture they pass downward and to the right to the middle of the whorl, where they are deflected perpendicularly to the suture below ; over each whorl pass raised spiral lines, often slightly larger and farther apart on the central part of the whorl ; body whorl showing ribs above, which die out below ; spiral stria- tion over whole volution ; besides the humeral angle a pronounced though not sharply carinated angle appears on the body whorl about twice as far below the humeral angle as the latter is below the suture ; mouth parts and columella Levifiisus-XxV.^. Localities. — Pendleton, Texas ; Marthaville, I,a. Named in honor of the finder, Mr. A. C. Veatch of this survey. Cancellaria quercollis var. greggi. Plate 54, fig. 3. Syn. — See Bull. Amer. Pal., vol. 3, p. 26, pi. 3, fig. 6, 1889. We have but a small, fragmentary specimen of this species from Pendleton, Texas, but its markings are so peculiar that its identification is simple and certain. Buccinanops ellipticum. Plate 54, figs. 4, 5. Syn. — See Bull. .Amer. Pal., vol. 3, p. 30, pi. 3, figs. 14, 15, 1899. The specimens before us are small but seem to belong to this species. Localities. — Pendleton, and Sabintown, Texas. Pseudoliva vetusta var., Plate 54, figs. 6, 7. Syn. — Bull. Am. Pal., vol. i, p. 213 ; vol. 3, p. 31, pi. 3, fig 16. Two varieties of this species are present in the Lignitic of Louisiana. One, the form figured, is rather characteristic of the Lower Lignitic and Midway ; another with much callosity about the upper portions of the volutions is not uncommon in the form of casts. Localities — Pendleton, Tex.; Marthaville, La.; La Nana bayou. Volutilithes petrosus vars. , Syn. — See Bull. Amer. Pal., vol. 3, p. 33, pi. 4, fig. i, 1899. West of the Mississippi it seems to be the Upper Lignitic 3o6 Geological Survey of Louisiana [Sect. Sabinetown specimens only that show the peculiar callosity which often characterizes the L,ignitic specimens in Alabama. Localities — Sabinetown and Pendleton, Tex.; La Nana bayou ; N. E. of Sodus ; S. 2, 9 N., 12 W. The last mentioned locality may be Midway. I, 4. Ostrea pulasketisis 298 3IO Gkological Survey of Louisiana [Sect. Page Fig. 5 . Modiola stubbsi 298 6. Modiola stubbsi 298 Fusus harrisi 299 Leiostoma ( ?) ludoviciana 299 Turritella inorton i 299 Explanation of Plate 53 Page Fig. I . Ostrea thirscr .* 300 2. Modiola alabaniensis (Ala. specimen, taken from Bull. Amer . Pal . ) i' 300 3 . Barbatia cuculloides 301 4. Mactra bistriata x | 303 5. Leda aldrichiana x | 301 6. Venericardia planicosla x 4 302 7. Astarte smxthvillensis (Alabama specimen, from Bull. Amer. Paleont. ) 302 8. Tellina, n. sp x il 9. 10. Cardiiim tuomeyi, vars x 4 11. Kellia prima (From Bull. Amer. Pal.) 302 12. Pholas alatoideus (From Bull. Am. Pal.) 304 Explanation of Plate 54 Page Fig. I. Pleurototna silicata (From Bull. Amer. Pal.) 304 2. Pleiirotoniella veatchi , )i. sp. x. ^ 305 3. Cancelldria var., greggi (From Bull. Amer. Pal.) 305 4. 5. Buccinanops ellepticum (From Bull. Amer. Pal.) 305 6,7. Pseiidoliva vetusta var 305 8. f.evifiistis indentus (From Bull. Amer. Pal.) 306 9. Levifusus siipraplantis (From Bull. Amer. Pal.) 306 10. Levifusus pagoda (From Bull. Amer.- Pal.) 306 1 1 . Tritonidea pachecoi x 2 306 12. Mazzalina plena (P'rom Bull. Anier. Pal.) 306 Explanation of Plate 55 Page Fig. I. Nassa exilis (From Bull. Amer. Pal.) 307 2, 3. Fusoficula juvenis (From Bull. Amer. Pal.) 308 4. Turritella tnortoni " " ' 308 5. Turritella hunierosa " " " 308 6. Turritella priTcittcta " " " 308 7. Natica eminula " " " 308 8. A'atica aperta " " " 308 9. Natica alabajniensis " " " 308 10. Sigaretus declivus " " " 308 1 1 . Solarium bellense " " " 309 CEOLOGICAL SlRVEV OF LOUISIANA, REPORT, 1S99 Plate 49 See expla?iation, page jop. Geological Survey ok Louisiana, Report, 1899 Plate 50 See explanation, page jog. Geological Survey of Louisiana, Report, 1S99 Plate 51 6 — ? See explanation, page jog Geoi,ogical Survey of Louisiana, Report, 1899 See exp/auation, page ^09-10. Geological Survey of Lovisiana, Report, 1S99 Plate 53 See explanation, page j/o. Gkological Survky of Louisiana, Report, li Plate 54 See explanation, page 310. Geological S0Rvey of Louisiana, Report, 1S99 Plate 55 See explanation, page 310, special Report No. 7 THE ESTABLISHMENT OF MERIDIAN LINES BY G. D. Harris CONTENTS Prewminary Remarks The Compass Needi,e Variatio7is and imperfectiojis. .312 The Transit, with and without Solar Attachment Its use 312 Cost 313 Improvement of Compass Surveying Magnetic decliyiation ajid Need of meridian lines 314 its secular chajige 313 How established 314 Our Outfit and Experiences Meridian Lines Established Mansfield 317 Harrisonburg 320 Many 317 Shreveport 320 Natchitoches 317 Monroe 321 Colfax 318 Alexandria 322 Winnfield 318 Floyd 322 Columbia 319 Magnetic Declination Amou?it of " variation " determined by one com- pass 7iot applicable to work done zvith another . . 322 A fine field for magnetic work 32 3 THE ESTABLISHMENT OF MERIDIAN LINES PRELIMINARY REMARKvS The Compass Needle Variations and imperfections. — The propriety of using a mag- netic needle for determining direction in ordinary- land surveying is indeed questionable. When we know that so called ' ' variation of the compass needle " is changing from year to year (secular variation); when we remember that there is an annual variation, or change from season to season, and a diurnal or daily change ; when we observe the sensitiveness of the needle to extreme changes in temperature, its deflection by local attraction and magnetic storms, or its sluggishness from a worn center or loss of magnetism ; when finally we know that no non-reversing needle ever does indicate the exact magnetic meridian because its physical axis is never exactly the same as its magnetic axis ; then we must admit that even though the instrument is in perfect adjustment, the chances of laying off two coincident lines from any given starting point, at different intervals of time with one and the same com- pass are indeed slight. Different men with different instruments at different times, have naturalh', as we all know, come to very different conclusions regarding the location of many corners and boundary lines. Without going into details regarding the troubles thus brought about, it is more to the point to make inquiries as to how the present methods of determining direction can be improved upon. The Transit, With or Without Solar Attachment Its use. — No one who has ever become familiar with an engi- neer's or surveyor's transit can go back to compass surveying with any degree of satisfaction except in mere preliminary or recon- naissance work. Again, the ordinary transit is equipped with a needle, so that whatever merit may be in such a mechanism, is Ill] Special Report No. 7 : Meridian Lines 313 possessed by the transit as well as the plain compass. But the possession by a transit of a horizontal limb provided with verniers for laying off or reading angles directly to within a minute or less of an arc, gives it a superiority over the plain compass that no surveyor can fail to acknowledge at once. As time goes on and the price of land increases, there in a ten- dency to lay less and less emphasis on the actual direction the boundary lines of land bear to true north and south or east and west lines. Descriptions are based more and more upon cultural features the more such features increase. Points are fixed by their distances from other fixed points, the angle that two inter- secting lines make is measured with the transit, and such angles are recorded, while the true bearing of either line with the meridian is neither sought nor given. If, however, there is need of knowing accurately (sa}' to i ' of arc) the bearing of a line, it can be determined in the day-time by the same transit instrument provided it possesses a vertical circle with proper graduations and verniers. This is done by alt- azimuth observations on the sun. The solar attachment greatly lessens the amount of calculating involved, though it means more adjustments to care for. Cost. — The ordinary compass can be bought for from $25 to $50. A good transit costs at least $200 ; it cannot be carried in sad- dle-bags, nor can a limb or rail splinter be used as a temporary yet admittedly efficient support. Obviously, then, there is here a question of more money, time, care and attention at stake, points not readily and willingly overlooked by employer or surveyor. Yet, if the parish owned the instrument, and this it could well afford to do, and the surveyors were selected by civil service examination and given a small salar}^ in addition to their fees for each piece of work, there can be no doubt that in the long run thousands upon thousands of dollars would be saved and many life- long troubles averted. Improvement of Compass Surveying Magnetic declination and secular cha7ige . — Every surveyor knows that to follow certain lines established by one survej'or, say in 314 Geological Survey of Louisiana [Sect. 1820, he must run on one variation, and to follow another in the same region but established by a different surveyor with a dif- ferent compass at a different time he must run on a different var- iation. In other words, putting aside occasional outright poor work, the lack of a definite knowledge of magnetic declination and its secular variation on the part of the previous surveyors has often been the source of a vast amount of trouble, mental and financial. Unfortunately, even to-day, the surveyor with an ordinary compass has no readj^ means of determining the amount of this variation ; for to determine the number of degrees and minutes that the axis of his needle makes with a true merid- ian line means that the latter is already established or known. But such a known line does not exist in his parish, nor has he the means of establishing one. Need of meridiaji lines. — The above statements are sufficient to show that if compass surveying be continued, it is quite time that some systematic records be kept of what each surveyor means by " due north " or any other direction he gives, basing his statement on the direction assumed by his undamped com- pass needle. A well kept needle will usually settle twice within 5' of the same place. With proper care, it can be read to 5' of arc. Poor needles may mislead to the extent of 30' or more. A line then that is within i' of the true meridian of the place is sufficiently accurate for all compass work. Any higher degree of refinement, however desirable and satisfactorj- on general principles, is wholly unappreciated in compass surveying. How established. — But as before stated, such a line can be established by day whenever the sun is shining : or b}' night whenever the circumpolar stars are visible, to a still greater degree of accuracy' by a rather unpretentious engineer's transit. Instructions for this operation have been so frequently pub- lished in works and reports relating to surveying and surveys that it seems quite unnecessary to repeat them here. However we cannot refrain from suggesting that in place of the usual paragraph of instruction in night work which reads somewhat as follow: "Let an assistant place a light corresponding in brightness to that of the stars at a point seemingly exactly Ill] Special Report No. 7 : Meridian Lines 315 beneath Polaris at its elongation, or let him hold the fine point ot an illuminated pencil on a wooden plug or board fixed to the ground;" we would suggest placing an illuminating scale (see Fig. 7) at 600 to 1000 feet from the transit some little time before the elongation and then watch the star move in azimuth from I, 2, to say 8 and return. A fairly- good scale can be improvised as follows : Take a new piece of tin about 6x14 inches and cut slits at intervals of from .05 to .10 ft. according to the power of the telescope and the distance available. Fig. 7. — Illuminated scale for night work. Fractional parts of interspaces can be estimated to the nearest y^^ z. (?., o.oi ft., if the instrument has no micrometer attach- ment. When the scale is placed at such a distance as to cause one space to represent about 20", it follows that readings are made to about 2" of arc. If when the various readings have all been reduced to the elongation and there is no serious discordance shown, it is safe to conclude that the average is a close approxi- tion to the true elongation. Other circumpolar stars giving an opposite elongation the same night can also be observed with the scale reversed. The true elongation of eacl^ can be computed from the several obser- vations on the same, and all can be used in the final location of the meridian line. The position of the scale on the subjacent board should be accurately marked, and in the morning a fine, straight steel pin 3i6 Geological Survey of Louisiana [Sect. can be placed where the mean of the elongation readings was on the previous night and the azimuth of the stars at elongation laid off in order to establish the true north and south line. The position for Polaris and several other circumpolar stars is conveniently given for each day of the year in the American Ephemeris and Nautical Almanac. The latitude of the place can be determined with sufficient accuracy by an inspection of any good state map. Then ^, Sin. Polar Distance Sm. Az. at Elong.=,::^ — -. ^. , Cosine Latitude. The surveyor will find it greatly to his advantage to establish his meridian line in the day-time before his night work by equal altitudes, or ordinary alt-azimuth observations on the sun to within i' of arc. He will thus be able to have the monuments placed, but not cemented in, and will also have his scale placed already for illumination at night. The final lining up of the monuments is but a short task for the next morning. Where monuments are small and of local construction, there should always be four placed in line so that any disturbance in one can be detected by the rest. Our Outfit and Experiences We have only to add that our outfit for the past year consisted of a good Heller & Brightly engineer's transit, of high magni- fying power, but with verniers reading directly to minutes only. Great interest seemed everywhere to be manifest in the work and we are glad to say that during the coming year this work will be greatly facilitated by the use of an instrument of a much superior order of construction and refinement. With our present small staff, no considerable amount of time can be spent on work of this nature. It is for this reason we have suggested and urged co-operation with the U. S. Coast and Geodetic Survey. See Introduction. As will be seen below, we have been favored by Maj. Willard with careful descriptions of many of the Reference and Azimuth Points of several of the river surveys. Ill] Special Report No. 7 : Meridian Lines 317 Meridian Lines Established Mansfield General location. — Across (midway) west yard of Mansfield Female College grounds and % mile to south, in Mrs. Williams' field. Marks or monuments. — Three Lignitic, calcareous, concretion- ary boulders. N, at northern side of the college grounds, N', at the south side, and S, 1800 feet south of N, in Mrs. Williams' ' lot. Many Geyieral location. — In Mr. E. C. Dillon's lot west of residence. For detailed information call on either Mr. Dillon, or Dan'l Vandegaer, Esq., parish surveyor. Marks — Calcareous, Lignitic boulders. Only three in number. S, near a pine tree in Dillon's yard, west of house ; S', by the fence just north of stream, perhaps 300 ft. north of S ; N, in edge of field, 897 ft. north of S. Natchitoches General locatio7i. — Through Normal school grounds west of the buildings about 150 feet. Marks. — Calcareous Claiborne boulders ; exact meridian marked by drilled holes filled with lead plugs. The northern most, N, is within perhaps five feet of the northern line fence ; N' is south of N about 30 feet, S' is just south of the walk or road leading westward to the woods and S is within 3 feet of the southern line fence of the school grounds. Colfax General location. — Court house yard, east of Court house. See Mr. R. E. Mc Knight, Colfax, La. Marks. — Grand Gulf sandstone boulders ; all four within court yard limits. Definite marks consist of sunken lead plugs in sandstone. N and S are very close to north and south limits of the yard. 3i8 Geological Survey of i^ouisiana [Sect. Colfax Base Line Established by U. S. Engineers * " Colfax base line, tertiary triangulation of Red river, was in Grant Parish, La., near Colfax, but was marked permanently- only at one end ; the triangulation stations adjacent to south base at Colfax were permanently marked. " South base is marked by the point of a nail set in cement within the end of a vitrified sewer pipe. The pipe is 12 centi- meters in diameter and 75 centimeters long. The top of the pipe projects about i decimeter above ground and stands in a meadow just above Colfax. It is about 100 meters northwest of the row of cabins on C. H. Teal's place and about no meters northeast of the fence enclosing a small lot. " Elevation, 35.92 meters, [Cairo Datum.] " Latitude, 31° 29' 50". "Triangulation stations are marked in a manner similar to South base. "Azimuth, vSouth base to Sta. 260,77° 07'. Distance 801 meters. South base to Sta. 260a, 16° 55'. Distance 1093.6 meters. South base to Sta. 261, 333° 40'. Distance 1 160.6 meters." WlXN FIELD General location. — Court house yard, east of Court house. Marks. — Four limestone boulders from the " Marble Quarry." Exact mark consist of lead plugs, as elsewhere. N. and S. are near the north and south limits of the court yard. In case of doubt see Messrs. Dunn, Bailey, Wallace or any other citizen. Columbia General location. — Diagonally across Court house yard passing but a few feet west of the corner of the same. Marks. — Calcareous boulders. All four within the court yard limits. Line defined b}^ sunken plugs. In case of doubt as to location drop a card to A. J. Daniel, Parish Surveyor, Kelly, La. * The information here and elsewhere credited to the U. S. Engineers was very kindly furnished by Maj. J. H. Willard, Vicksburg, Mi.ss, Ill] SpeciaIv Report No. 7 : Meridian Lines 319 Line, Monuments, Etc., U. S. Engineers {Ouachita River Survey). '' ^ Permanent 7'eference line, Cohunbia, Ouachita River survey, is in Franklin parish, I,a., on the left bank of the river opposite the town of Columbia. Both ends of the line are marked alike by a 4 centimeter gas pipe about 1.6 meters long, with a cap on top, and a circular flange attached near the lower end by lock nuts. The pipe is bedded in cement and projects above ground about I decimeter. ' 'Permanent reference point is about 2.4 kilometers below Colum- bia, near the bank of Bridger Bayou. It is about 7 meters north of the front fence of the Ivy Davis plantation. Witnessed by three trees with triangular blazes, as follows : "Double China berry, 0.4 meter in diameter, 29 meters, 77° 00'. China-berry 0.4 meter in diameter, 19 meters, 131° 45'. China-berry 0.3 meter in diameter, 16 meters, 143° 55'. Northeast corner of a cabin, 24.5 meters, 126° 45'. Elevation of cap, 27.01 meters," [Cairo Datum.] ''^Permanent azimuth point \s on the main top bank of the river opposite Columbia, near where the road from the ferry comes out of the woods, and joins the main road. It is north of the plan- tation fence and aboiit 7.5 meters from the main road. It is about 30 meters east of a cabin and about 260 meters west of St. Peter's church. Witness trees blazed with triangular blazes as follows : " Sweet Gum, 0.5 meter diameter, 19.5 meters, 356° 45'. lyocust, 0.3 meter diameter, 6.8 meters, 310° 00'. Locust, 0.3 meter diameter, 6.4 meters, 109° 05'. S. W. Corner St. Peter's Church, 291° 29'. Azimuth, P. R. P.— P. A. P., 94? 49'." Harrisonburg General location. — Main line on Mr. E. D. Spann's property passing just east of his house. Marks. — Grand Gulf sandstone boulders, with lead plugs. N', in front of Mr. Spann's house, 5 feet south of the north yard fence ; N' by fence at N. E- corner of house ; S and S' are near the edge of the field on either side of a little branch, about 360 to 380 feet south of N'. Two boulders in the school house j^ard 320 Geological Survey of Louisiana [Sect. one by the fence E. of the school house yard, one by the fence south of the same building mark an east and west line. The westerly side of the new brick jail has a bearing of N. 14° 32.7'E. Line and Monuments ±Lstablished by U. S. Engineers Near Harrisonburg ^' Permanent reference line, Bushley, Ouachita River survey, is in Catahoula parish, La., on the right bank of the river, about two kilometers below the town of Harrisonburg. The line is marked by a gas pipe in a manner similar to P. R. L., Columbia. Permayient reference point is about 200 meters south of the mouth of Bushley bayou, at edge of wood-line, and about 325 meters back from right bank of river. Witness trees blazed with triangular blazes, as follows : Maple, 0.4 meter diameter, 18 meters, 320° 30'. Pecan, 0.3 meter diameter, 21 meters, 14° 00'. Cypress, i.o meter diameter, 6 meters, 265° 45'. Elevation, 24.20 meters, [Cairo Datum.] ''Permaftent azimuth ^(7m/is about midway of old Scott planta- tion, on large mound (first near river above Bushley bayou), about 140 meters back from right bank of river. Witness trees, blazed with triangular blazes, as follows : Honey Locust, 0.2 meter diameter, 8 meters, 340° 45'. Sweet Gum, 0.2 meter diameter, 13 meters, 110° 20'. 3weet Gum, 0.4 meter diameter, 19 meters, 240° 05'. Azimuth, P. R.P. to P. A. P., 155° 43'." Other Localities Where Azimuth Lines are Established by the U. S. Engineers Shreveport base line, tertiary triangulations of Red river, is in Bossier parish, La., on the left bank of Red river, opposite the town of Shreveport. Both ends of the base are marked alike with an underground stone slab and iron pipe rising above ground. The underground mark is a piece of limestone 46 cen- u.s. . timeters square, and 15 centimeters thick, marked o with a spherical headed copper bolt leaded in the center of the upper face. The pipe is cast iron, 12 centimeters in diameter, and 1.2 in] Special Report No. 7 : Meridian Lines 321 meters long and stands on top of the stone. The pipe is covered by a cap which is fastened on by a bolt and nut. There is a small boss on top of the cap, with a hole in the center. Northwest base is now buried under the front slope of the levee, about 20 meters from where the levee crosses the embankment of the V. S. & P. Ry., about 300 meters from the northeast end of the bridge across Red river. A wooden post stands on top of the pipe, and projects above the surface to mark the location. Southeast base is on the field side of a fence on the north side of a lane running down the river near the left bank, and it is about 200 meters east of the turn in the lane and 150 meters west of the house of C. M. Dougherty. Length of base, 704.34 meters. Azimuth, N. W. B.-S. E. B. 296° 45'. Latitude of N. W. B., 32° 31' 38". Elevation of bolt in stone marking N. W. B., 58.37 meters. Elevation top of cap N. W. B., 59.61 meters, [Cairo Datum.] Elevation top of capS. E. B., 59.83 meters, [Cairo Datum.] ^ ' Permanent refereyice line, Monroe,\s in ouachita Parish, La., on the left bank of the river and lies along De Siard street in the town of Monroe. Both ends are marked alike by a piece of " T " rail set in the ground with the top buried about 0.03 meter below the surface. The head of the rail has a cross on it, marking the point. ' ' Permanent reference point is near the west end of De Siard street, and about 28 meters from the river bank. It is on line between a cross cut on Merchants' & Farmers' Bank and one cut on the Block building. It is 3.84 meters from the first and 8.7 meters from the last. The cross on the bank building is 9.36 meters from the angle in the wall beside the door ; that on the Block building is 14.32 meters from the front line on Grand street. Elevation, 30.83 meters," [Cairo Datum,] " Per^nanent azimuth point is 5.6 meters from the iron fence around the Monroe cemetery and 30.5 meters from the corner at the gate. Witnessed as follows : Spire (Col'd) Methodist church, 225° 01'. Spire (Col'd) First Baptist church, 121° 56'. Index finger on monument to Margaret J. Henderson, 9° 32'. 322 Geological Survey of Louisiana [Sect. Azimuth, P. R. P. to P. A. P. 232° 52' 47". Alexandria base line, tertiary triangulation of Red river, is in Rapides Parish, La., on the right bank of Red river and behind the town of Alexandria. Both ends of the base are marked alike with stone and pipe similar to the Shreveport base line. " Northeast base is in a meadow about 50 meters southeast of a barn. ' ' Southwest base is in open field on a low levee about 50 meters east of fence. Length of Base, 955.676 meters. Azimuth, N. E. B., to S. W. B., 81° 48'. Latitude, N. E. B., 31° 17' 47". Elevation top of cap N. E. B., 30.21 meters, [Cairo Datum.] Elevation top of cap S. W. B., 31.58 meters, [Cairo Datum.] ''Permanent reference line, Floyd, Bayou Macon survey, is in West Carroll Parish, La., on the right bank of the Bayou in and below the town of Flo3^d. " Permanent reference point \s marked by a 4 centimeter gas pipe with a sleeve on the upper end, driven in the ground about 400 meters below Floyd on Mrs. Emma White's place. It is about 150 meters west of bayou bank, about 10 meters west of edge of hills, about 200 meters southeast of dwelling, 44 meters south of cabin and 27 meters north of fence. ''Permanent azimuth poiiit is the cupola of the Court House in Floyd. Azimuth, P. R. P. to P. A. P., 161° 46'. MAGNETIC DECLINATION Amount of ' ' variation ' ' determined by one compass not applicable to work do?ie with another. — There are in all compasses and tran- sits strong probabilities of a certain error in their readings of mag- netic bearings owing to the fact ist, that the line of sights is not exactly in line with the zero marks on the compass box and 2d, that the magnetic axis of the needle does not exactly co-incide with its physical axis. Thoug^i we made a number of readings at various parish seats and elsewhere and though we took the precaution to determine the amount of index error of the transit used, yet we feel that Ill] Special Report No. 7 : Meridian Lines 323 such readings are scarcely worthy of publication, and for the following reasons : The results though correct would not be directly serviceable to local surveyors using their own instru- ments, and, to be of service in purely scientific work, the amount of declination should be determined by a magnetometer specially constructed for such work. And again, the dip and intensity or total magnetic force should be determined in order to advance the cause of the science of terrestial magnetism. A fine field for niag?ietic work. — The complicated geologic structure of Louisiana is just beginning to be realized. Gener- alities based on trans-Mississippi investigations, and smooth, straight lines separating the different series and stages will soon be relegated to the past. It is mainly through invertebrate pale- ontology that the relationships of the various formations repres- ented in the State are and have been determined. Yet if we mistake not, paleobotany will soon be able to lend a hand in this work. Possibly too magnetic investigations may throw some light on stratigraphy. Be that as it may, it is certain that the smooth agonic lines heretofore drawn through Louisiana will be crumpled and curved in a marked fashion when they have been platted from a large number of field observations. Witness : At Many decl. about 7° ; Natchitoches, 6° 40' ; St. Maurice, 6° 35' ; Couley, 6° 40' ; Winnfield, 6° 45° ; Columbia, 6° 10'. January and February, 1899. Have the results of orographic movements so manifest about Winnfield anything to do with the irregular declination there shown ? In Louisiana, as well as other States laid out in rectangular townships, sections, etc., the question of latitude, so essential in rapid and accurate magnetic survey work is often quickly deter- mined with sufficient accuracy by asking any resident what sec- tion he is in, or by inspecting his deeds or tax receipts, and having him point out the locations of the various "quarter quarters" called for. Yet there are places occasionally where there are no inhabitants for 15 or 20 miles along the main roads. 324 Geological Survey of Louisiana [Sect. Here the road maps mentioned in our next article would serve an excellent purpose, enabling one to locate himself at any time with accuracy. A magnetic survey of a state should include at least one observation in every township. The greater the facility with which trustworthy observations can be made, so much the less expensive and more accurate will be the results. special Report No. 8. A FEW NOTES ON ROAD MAKING BY G. D. Harris CONTENTS Literature Office of road inquiry 326 Practical instruction 326 Location of Roads No surveys yet made 327 Monuments 327 Other objects of road survey 327 Road Material, 328 Roads and Road Machinery, 328 A FEW NOTES ON ROAD xMAKING Literature Office of road mqiiiry. — Fortunately for those interested in the construction of good roads, the Department of Agriculture at Washington, D. C, has instituted an " Office of Road Inquiry" under the able direction of Gen'l R03" Stone. This office has collected a large amount of valuable information and published it as bulletins and circulars, and has distributed copies of the same, free to those interested in the subject. The titles alone are sufficient to show the scope and impor- tance of this " inquiry." Note the following : Bulletin No. i. — State laws relating to the management of roads, enacted 1888-1893. Bulletin No. 18. — (Supplement.) State laws relating to the management of roads, enacted 1 894-1 895. Bulletin No. ly — Historical and technical papers on road build- ing in the United States. Bulletin No. 12. — Wide tires. Laws of certain States relating to their use. and other pertinent information. Bidletin No. p. — State aid to road building in New Jersey. Bulletin No. 16. — Notes on the employment of convicts in con- nection with road building. It seems entirely unnecessary here to give even an abstract of these and other important papers since they are so readily obtained, by addressing the Office of Road Inquiry at Washington. Practical instncdion . — The easiest, quickest and most satisfac- tory way of learning the art of good road making is to watch those who understand and are actually engaged in making roads. It was hoped and even announced that Mr. Harrison of the Washington bureau would oversee the construction of a model road from the North Louisiana Experiment Station to Calhoun Station soon after the meeting of the Agricultural Society at Shreveport. Circumstances were such, however, that Mr. Har- rison could not then leave Washington to take charge of the work and the matter was postponed. Ill] Special Report No. 8 : Road Making 327 Location of Roads No surveys yet made. — The vast majority of Louisiana roads seems never to have been properly located. Thej^ represent enlarged trails. The)^ are, within certain broad limits, wherever each season the traveling public sees fit to go. Observe the broad band of land on either side of most any old or well recog- nized road and count the different road beds of tens or scores of years ago now recognizable as narrow long ditches and frequently overgrown bj- forest trees. Look again at the several lines of log roads ("causeways") that can be seen running along paral- lel to each other across marshy stretches. Is there any real incentive to do thorough and lasting work on a stretch of road that may soon be paralleled by a new one, simply because the old one somewhere had one impassable spot ? Right here we believe is the place to begin. We have urged each parish survej'or and all others who manifest an interest in the subject to see at once that at least the "first class " roads are located. This should be done by giving the distance from the nearest section corner at which the road enters each section and the traverse through the section. This information would, of course, be recorded at the parish seat. Momcments. — Stone or iron posts could well be used at the road-sides to indicate the crossing of section lines, and certainly permanent monuments should be carefully located on either side of the road at each angle. Other objects of a road survey. — I believe the benefits to be derived from a road survey can scarcely be overestimated. It would establish a network of known points and distances through- out each parish that would be a most welcome guide to all travelers, be they geologists, botanists, timber men, commercial travelers, pleasure seekers, produce shippers or home seekers. It is no exaggeration to say that a geological survey could be prosecuted with double the despatch and double the accuracy if the roads were only located and mapped. Other public and private works would be likewise benefited by the mere location of roads. Add to this, the increased facilities of a road bed well made and well maintained, and the annual benefit, direct to the 328 Geological Survey of Louisiana [Sect. traveling public, indirect, though far greater to the resident would be almost beyond calculation. We have already noted the fact that as time goes on cultural features are used more and more for reference points and lines in the description of real estate. Here then is another reason why roads should be well located. For the future will see many of these very roads used as boundary lines between subdivided estates. Road Materials The common country roads through Louisiana will naturally be for some time to come "dirt roads." There are however, favored localities where shell and gravel can be freely used for ballast. In section II of this report under "Lafayette" (pp.ioo- 104) numerous localites are given where quartz pebbles occur. In some few cases they are sufficiently abundant to be easily obtained in quantity, and will doubtless be shipped to a consider- able distance for road- making in the near future. So far as dirt roads are concerned their construction and main- tenance has been greatly simplified of late by the introduction of road machinery, and we close with the following paragraphs from circular No. 31 of the Office of Road Inquiry. If they have already been read, they certainly will bear reading again. Roads and Road Machinery The first thing to be observed in building conntry roads is to afford pro- tection against water. A dirt or gravel road properly built and maintained can be made to shed water like a roof, and if the use of narrow tires and the wearing of ruts could be prevented, our country roads might be excellent. Water always runs down hill, and this should betaken advantage of in road building. If the road be properly crowned, that is, if its middle be properly- raised above the sides, the rain and melted snow will naturally run off into the ditches. On the other hand, if the middle be worn down by travel, the water collecting there will soon form a puddle, and ruin the road. In the same way, ruts formed by narrow tires afford a trough for the collection of water, and contribute to its destruction. Labor as they might, American farmers have long been unable to build their roads so as to shed water. But the solution has been found in the road grader. The American farmer is quick to realize the value of machinery, and the rapid growth in the use of the reaper, the binder, the separator, is ail eloquent tribute to the practical genius of American agriculture. The Ill] Special Report No. 8 : Road Making 329 growth of the use of road graders has been wonderful during the last few years, and indicates that the farmer has discovered a practical solution of the problem how to build his local dirt roads. The peculiar feature of a road grader is that it cuts away the dirt at the side of the road, and draws it up into the middle, thus producing a ditch at each side and a slope in each direction from the center. At the same time it will cut awa)^ the dirt to just the proper depth, and no deeper. In this particular, its work differs from that accomplished by the use of plows, shovels or hand scrapers. The road grader leaves a smooth, regular surface, giving the road the proper contour. A dirt or gravel road can be put into excellent shape by running the grader repeatedly over it. Care should be taken first to remove brush and rubbish from the side of the road, that the grader may not carry it into the traveled roadway. To properly finish a dirt road made with the use of the grader, it should be thoroughly rolled and hardened. It is not sufficient that it be crowned, but it should be made hard and smooth. The same thing is true of gravel roads. This can be best accomplished with the use of rollers. Horse rollers weighing from five to eight tons are most frequently used for the purpose. All loose stones should be removed from the road surface before rolling, as well as sods, turf, leaves, sticks or any other matter that will tend to soften the road bed. A road that is thoroughly and repeatedly rolled is well fitted to stand the wear of travel, and can be made into a perfect watershed. The difficulty about the use of road machinery in many localities is to be found in its cost. It is frequently thought wrong that farmers should be obliged to tax themselves for the purchase of road graders and road rollers, in addition to having to stand the regular road tax. There is much justice in this position, for the average farmer pays his full share of taxes, and these should not be added to or increased without some very excellent rea- son. But the farmers of the United States are badly in want of good roads, and the clamor for their construction is growing from year to year. Quite a number of towns have solved the road machinery problem by voting to pay their taxes in cash instead of working them out, and using a parts of this fund for the purchase of machines, which avoids the necessity of levying an extra tax for the purpose. This plan has been adopted in New York and Wisconsin, and probably elsewhere. The town of North Salem, Westches- ter Co., N.Y., adopted itasfar back as i88r. The town of Canaan, Columbia Co., N. Y., adopted it in 1887. In Wisconsin, C. H. Everett, until recently the president of the Wisconsin Dairymen's Association, says on this subject in a recent letter : " The town of Turtle, Rock County, where I reside, was among the first to adopt the cash system, and has two improved road graders. I do not think that our people could ever be induced to go back to the old system. We know that we have spent enough money in road taxes during the past fort}- years to have macadamized ever}' road, and until we began to pay our road taxes in cash and use machinery, there had been little or no improvement in our highways." 330 Geological Survey of Louisiana [Sect. The proposition to pay road taxes in cash met with little favor in the beginning. Farmers were unwilling, as might reasonably be expected, to pay their road taxes in cash instead of in work. But sentiment is now largely the other way among intelligent farmers, since experience has shown that more can be accomplished with one dollar of tax paid in cash, than two dol- lars or even three dollars of tax worked out on the highway. Where the system has been fairly tried, farmers have found it by no means the burden expected, since they may still be hired by the road officers to run the machinery used. Two cases in Wisconsin are instructive on these points. Martin J. O'Malley, chairman of the town of Westport, Dane county, writes : '• We adopted the money system in the town of Westport two years ago. We purchased a good road grader, and we levied a 2-mill road tax instead of the 4-mill tax that we had been pa3'ing working the old way. The people are allowed to vote on the qviestion at every election, and they are fully convinced that the cash system is the only true way of getting good roads. There has been more work done on our roads during the past two years than in twenty years before." The same experiment was tried in the town of Middleton in the same county, and with the greatest success. In 1894, under the new law passed the 5^ear before, the town paid its road taxes in cash, and used part of the money for the purchase of two road graders. Wm. F. Pierstorff, chairman of the town, told of their experience in an address delivered at Watertown, in the spring of 1896. "Under the old laws," says Mr. Pierstorff, "we always levied a road tax of 4 to 6 mills. In 1890, a tax of 1^2,297.80 was levied ; in i89r, 13,346.70; in 1892, $2,326 77, andin 1893, 12,471.93. In 1894, the first year under the new law, we levied 2 mills, amounting to $1,051.58, and bought two road graders. We gave the farmers a chance in handling graders to work at three dollars per day with team, they giving us ten hours for a day's work. In 1895 we levied 2 mills as before, and expended $1,231.56 for our regular work on the highway. You will see that for the last two years we expended for general highway purposes an average of $1,141.57 a year, while the average for the preceding four years was $2,827.28. It is admit- ted by all that there was more w'ork done in the last two years than the town has ever done before. You can do more work with three teams and one grader in a day than with three teams and a small scraper in a week. Our people are well satisfied with the new system, and they will never vote to go back to the old method of working the highway." For the most recent exhaustive treatise on roads, road-making and road materials, see Rept. Geol. Surv. Md., Vol. III. Special Report No. g SOME WOOD-DESTROYING FUNGI BY Prof. Geo. F. Atkinson CONTENTS Study of Fungi in General Fungi on Garden Vegetables Fungi on Forest Trees POLYPORUS BOREALIS Page Page Occurrence and distribution .^-^^-^ How the tree is killed 334 Characters 333 Starting oftheftingusgcriu . 334 How nourished 333 Fruitage 335 Hydnum septentrionaltj Characters a7id distribution . . 335 FOMES FOMENTARIUS Characters ayid distribution . . 335 Trametes pini Characters and distribution . . 337 D^dalea ambigua Characters 337 Accidents in growth 338 Importance of a Study of These Fungi SOME WOOD-DESTROYING FUNGI STUDY OF FUNGI IN GENERAL Fungi on Garden Vegetables During the past ten years or so a great deal of attention has been given to those low forms of plant life known as fungi, which cause diseases of farm and garden crops. These investiga- tions have made us familiar with the history of many of these enemies of the farmer and horticulturist, and have taught us how in many instances to successfully combat them. This has resulted in the prevention of great loss, and taking the country over, thousands of dollars each year are now saved by the practi- cal application of the knowledge gained by studies of the fungi. Fungi on Forest Trees Very little attention, however, has been given to the study of those forms of fungi which attack forest and timber trees, although the National Government for a number of years has been engaged in propagating information along certain lines of forestry work, and in an endeavor to arouse general interest in the question of the preservation of forests, as well as in the establishment of a rational method of timber cutting, which shall protect the young growth and provide for future crops of timber. The number of fungi which occur on living and dead trees in the forest is verj^ large, and the damage which is caused by them in producing the decay of fallen timber, of cuttings, and especially in causing heart rot of many valuable standing timber trees is very considerable. When one begins to observe these wood destroying fungi in the forest, one is impressed with the great variety of form which they possess, indicating that there are many species or kinds- They stand out as brackets or shelves from the trunks of trees, from the sides of fallen logs, from old stumps, or even from the ground where they are growing from some decaying wood in the soil, or perhaps from some diseased root. Some of these plants are fleshy and soft in consistency, so that they soon disappear. Others are more or less tough, and dry up considerably during dry weather but expand again during rains. Still others are of Ill] Special Report No. 9 : Fungi 333 quite a woody or cork}^ texture, often very hard. Many of these latter ones live from year to year so that they are perennial. This article is written for the purpose of calling the attention of those who frequent the forest, either from a professional or from a pleasure point of view, to these enemies of the forest. There are many problems of interest and importance presented by the relation of these plants to the timber trees. A few of these problems are suggested by the description of several of these plants. Polyporus borealis Plate 56 Occurrence and distribution. — The first one of these plants to which attention is called here is very active in causing one kind of heart rot of coniferous trees, especially the spruces, pines, balsams, hemlocks, etc. It is known as the Polyporus borealis. It has a very wide distribution not onl}^ in Europe and in America, but probably in other countries as well. A photograph of this fungus attached to a living hemlock tree is shown in Plate 56. This tree occurred in one or the deep wooded ravines at Ithaca, N. Y., along one side of the Campus of Cornell Universit}-. Characters . — The fungus is white and is of the bracket kind. As can be seen, there are several brackets growing very closely together overlapping each other. The bracket is the "fruit body." While these plants have no fruit in the sense that the higher plants do, yet they produce countless tiny bodies, called spores, so minute that we cannot see them except with the aid of a microscope, or unless there are a large number of them massed together. These spores are capable of starting a new growth of the fungus. They are borne on the under side of the fungus, in minute pores or tubes which are so numerous that the under surface of the bracket reminds one of a honey- comb structure. The upper side is hairy with coarse strands which bristle all over the surface. It is rather soft and spongy. How nourished. — It will be of interest to know how such a fungus attached to a living tree obtains its food from the tree, and also how it is enabled to cause the decay of the heart wood. In the first place the fungus is growing from quite a large wound in the side of the tree. The tree has been trying to heal over the wound for years but it has not been successful, for the wound is a large one. The healing process, however, 334 Geological Survey of Louisiana [Sect. advanced quite far as can be seen by the new growth all around the edge of the wound. How the tree is killed. — Two years ago when I first observed this tree though it was still alive, a number of the top limbs were dead. This suggested that the rot caused by the fungus extended entirely through the tree. To determine this question, and also to see the relation of the fungus to the decay, as well as to determine the structural peculiarities produced in the wood by this species, during its disintegrating action on the wood, the tree was felled and sawed up into short sections. These sections were then split and a large number of them were preserved for examination. Several of the blocks of heart wood split from the tree were photographed, and one of these is shown natural size in Plate 57. The white strands which extend horizontally in the wood are the strands of mycelium which is the vegetative part of this fungus. It corresponds to the so-called "spawn " of the mush- room, which is characteristic of all the members of the fungi belonging to the mushroom group, though there are varia- tions in its nature and extent. These strands of the mycelium are composed of numerous delicate, slender fungus threads all woven together. They extend throughout the length of the tree in the heart wood. They grow through the cell walls of the wood and cause the disintegration of the latter, first by opening minute holes along the line of their advance, which is in a longitudinal, radial, and tangential direction. This tends to divide up the wood into small cubical areas which are more pronounced later as the fungus threads disappear and the wood by advanced stages of decay tends to collapse. The fungus threads have the property of excreting a kind of ferment which dissolves the woody and cellulose walls, thus disintegrating the wood and opening a way for the advance of the fungus. Starting of the fungus germ. — By this thorough examination of the felled tree it is possible to make out the history of this fungus. The photograph in Plate 56 tells a great deal of the story of how the fungus was able to get inside of the tree and then to grow out again in the form of the bracket fruit bodies. The Polyporus borealis is not a parsitic fungus. It cannot make its way unaided through the sound living part of the tree which Ill] Special Report No. 9 : Fungi 335 lies just beneath the bark. The heart wood of the tree is dead, so that the fungus when it once gets in there can perform its destructive work. The living wood, just underneath the bark, when it remains unbroken or unharmed forms an impassible bar- rier to the entrance of the fungus. How then did the fungus first get into the heart wood of the tree? The photograph tells us something of that. There is an old decaying log lying at the foot of the hemlock tree. Twen- ty-five or thirty years ago this log was a standing tree. It fell, and in its descent it struck the projecting base of the hemlock and knocked off the bark and living wood from quite a large area, two to three feet in length and a foot or more in breadth. The wound was so large that it could not heal in time to prevent the entrance of the wood destroying organisms. Furthermore, the bruised tis- sues would afford a secure lodgment for these germs. So here was formed a most favorable infection court, or area. During damp weather bacteria and fungus germs, the chief producers of the decay of organic matter, lodging here were enabled to get a foothold and start the disintegration of the wood. Among them were the spores of this Poly poms borealis. These spores pro- duced the delicate mycelial threads, and by the ferment action of their products these threads gained access to the heart wood, where there was an abundance of moisture for growth during the entire season. From this point mycelium spread upward and outward as it advanced through the tree. Fruitage. — After a number of 3^ears, when the decay had extended far up in the tree and a large quantit}^ of the spawn or mycelium strands had formed, reaching a large feeding area, there was a sufficient amount of food within reach to form the bracket fruit bodies which can only be formed in the open air. This same wound then provided a place of exit for the fruiting stage. The spores formed over the honej'-combed area are scat- tered by the wind, and are ready to infect other trees when an opportunit}' comes. HydMum septentriouale. Plate 58 Character and distribution. — In Plate 58 is illustrated another fungus growing on a living sugar maple tree. This is also one of the bracket or shelving fungi. Its natural size is about eight 336 Geological Survey of Louisiana [Sect. times larger than appears in the picture. While it is one of the bracket fungi it differs from the Polyporus in that the fruiting under surface is not in the form of a honey-comb, but is covered with spinous, or awl-shaped processes. This fungus grows in the heart wood also, and the interior portion of the tree was so badly decayed that the fungus was enabled to push its way out through a long crack which occurred through the living area. This tree was one of a grove of trees in Elysium Park, Cortland, N. Y., and was so weakened by the action of the fungus that it was blown down during a severe southeastern gale which swept over this area during the autumn of 1897. This fungus also occurs in other parts of the United States, and is widely dis- tributed in Europe, where it also occurs on the maple. Fomes fomentarius. Plate 59 Chatader and distribution . — During the same gale a large num- ber of trees weakened by the attacks of the wood destroying fungi were blown down in this region. Plate 59 represents a beech tree weakened by wood destroying fungi near McLean, N. Y., which was broken over at this time. Upon the trunk can be seen several of the brackets of one of the species, the Fomes fomentarius . Its fruiting under surface is honey-combed, but it is very different in habit, texture, form, and color from the Polyporus borealis. The brackets are scattered and usuallj^ occur singly, so that several do not overlap. The plant is shaped more or less like the hoof of a horse, small where it is attached to the tree, and then enlarged outward and downward. The under surface is more or less concave, with the thick margin pro- jecting somewhat like the edge of a horse's hoof. Furthermore, the surface is marked by a number of concentric ridges, and fur- rows, marking off the age of the bracket in years. The plant is perennial, and each year a new la^^er is added on below, which is broader than the layer of the previous year. The outer sur- face is light brown or grayish in color and thus harmonizes with the color of the beech bark, while the under surface is rich brown in color. The plant is quite hard and woody, especially the outer portion, while the inner portion is more spongy and fibrous and dark brown in color. The inner fibrous portion in years gone by was used as a tinder in some parts of Europe. m] Special Report No. 9 : Fungi 337 The plant is widely distributed on both Continents, and occurs also on the birch, maple, and other deciduous trees. Trametes pini Plate 60 Character and disirihition. — Another wood destroying fungus shaped something like a horse's hoof, but much more irregular, is the Trametes pini shown in plate 60. This photograph is taken from a specimen on a pine log collected by Professor Harris near Mansfield, Louisiana, during the winter of 1898-99, The fruiting surface here is also honey-combed, but there are other characters which place it in the genus Trametes, instead of \u Polyporus ox Fomes. This plant is also perennial and each consecutive ring represents a yearly layer added by growth, the lowermost layer being that of the last year's growth. This fun- gus occurs on pines in Europe, and also in the southern and southwestern United States. In Europe it is known to produce a characteristic and serious disease of the timber pines. Daedalea ambigua Plates 61 and 62 Characters . — Another very interesting fungus is that shown in Plates 61 and 62. It is the Dcedalea ambigua, also sometimes called the Trametes ainbigua. The honey-combed fruiting surface here is very irregular, sometimes the tubes or pores are cylindrical with roiinded mouths, and again they repre- sent elongated or sinuous passages, the round ones illustrating Trametes while the elongated or sinuous ones illustrate Z?Wa/^a. Since the plant in this character varies from one to the other, it is rather " ambiguous " as to which genus it appertains, and so it was named Dcedalea ambigua. This plant was also collected by Professor Harris in Louisiana. It is whitish in color, of a very beautiful appearance, grows on several different deciduous trees, and forms a true single shelf. An individual illustrated in Plate 61. is an abnormal form and shows to us one very interesting peculiarity of all these plants. The figure to the left represents the position in which the fungus grew when the tree to which it was attached was standing. At this time the broad single shelf was formed so that the shelf was horizontal, or parallel with the surface of the earth. This is a peculiarity of all the bracket fungi, and of 338 Geological Survey of Louisiana [Sect. the mushrooms as well. The fruiting surface being the under surface generally, the plane of the cap or pileus is parallel with the surface of the earth, so that the spores of the fungus can fall easily out of the tubes, or from between the awl-shaped pro- cesses, or from between the gills or lamellae, as the case may be. Accidents i?i growth. — Now, if by any chance the bracket, or cap, becomes turned in another direction before the fungus has completed its growth, it will either change back, as in the case of the mushrooms, or new growths will start out from the edge of the bracket in the tough or woody forms. Now, if we examine Plate 62 of this Dcedalea, we shall see the position of the plant after the tree fell. Since the entire edge of the large bracket was still in a growing condition there are established a large number of growing points, each of which develops a new bracket parallel with the surface of the earth, forming a series of steps up one side and down the other. Importance of a Study of These Fungi From a few of the observations here presented it will be seen how some of these fungi work serious injuries to forest and timber interests. The trees which are attacked may live on for years or even for a century or more, but each 3'ear the injury to the timber in the tree is greater, until within a few j^ears it is worthless. A careful study of the conditions of attack b}' these enemies of the forest, as well as of their life histories, and the characteristic injuries to the trees would do much to teach us how to prevent such injuries and loss in the forest. The wonderful variety of form and kind among these plants make them objects of great importance to those who are interested in nature. There is here a great field for new observations on the part of those whose professional work leads them to the forest When such persons become interested enough in these questions to prepare themselves for making accurate observations, by some training in the study of fungi, they can do great good in bringing to light a fuller knowledge of the habits and dis- tribution of these plants, and careful study by trained observers must precede any successful attempts toward a rational treatment designed to lessen the losses now sustained from these sources. Geological Survey of Louisiana, Report, iS Plate 56 POLYPORUS BOREALIS (Growing on hemlock.) Geological Survey of Louisiana, Report, 1899 Plate 57 ,, Iff iM^f, .ilWf'm'i]l~liiiif«r! III HEARTWOOD SHOWING MYCELIUM Geological Survey of I.otisl^na, Report, 1S99 Plate 58 HYDNUM SEPTENTRIONALE (Growing on sugar maple.) Geological Survey of Lovisiana, Report, 1899 Plate 59 FOMES FOMENTARIUS (On beech.) AA INDEX Aboriginal Works, Caddo Bottoms 201 Achatina 20 Attakapas Prairie 257 Alluvium and recent costal formations. 117 Altitudes in Northern Caddo parish and adjacent portions of Bossier. Dictionarj- of 203 Andromeda delicatula PI- 45, 287 Andromeda eolignitica PI. 47, 287 Angiospermcc 279, 280 Apocynacece 288 Apocynophyllum sapindifoliiuu PI. 46, 288 AquifoliaceiT 285 Aralia 281 Area cuculloides 301 viississippensis 32 rhonboidalis 77 Arcadia 84 Clays, described b}' Lerch 40 Well section at 84 Arick's mound 202 Artesian wells of Calcasieu, discussed by Hilgard 23 Artocaipus dubia PI- 38, 28 1 lessigiana PI. 37- 281 pimgens PI. 38, 281 Astarle smithvillensis PI- 53. fig- 7. 302 Atkinson , Geo. F 33 1 Avellana bullata 296 Avery, John Marsh PI. 20, opp. p. 216 Baciilites anceps PI. 5 1 , fig. 6, 297 Barbatia cuculloides PI. 53, fig- 3. 301 Bartram 12 Basilosaurus 17 Bayou Chicot limestone 61 Bayou Toro 9°. 129 Belle Isle 138. Archaeology 229 Contour map of salt deposits PI. 24, opp. p. 232 Discovery of salt 222 Fossils 224 BB 340 Index Belle Isle Geology 223 Location 221 Section of hole No. 12 227 Section of hole No. 13 228 Section of sand pit 224 Section of shaft 225 Topographic map of PI. 21, opp. p. 217 Topograph}' 22 1 Well sections PI. 22, opp. p. 225 f^eleninites 17 Bellevue S6 Section at 86 lienchmarks, U. S. E 20S Bernard 16 Bienville parish 83 Bistineau salt work 1 24 Black bayou 155 swamp, Origin of 169 Black lake 77 bayou 155 bayou gravel train, The 102 Section near 78 Bluff, wave-formed PI. 17, opp. p. 176 Bossier parish 85 Bottom lakes, Classes of 183-188 Origin of 1 83 Boyce 130 Breaux Bridge . 138 Breazeale spring 148 Chemical analysis of 148 Buccinanops elliptictim PI- 54, figs. 4,5, 305 Building stone 130 Caddo parish. Map of northern PI. 16, opp. p. 169 Calcareous soil 147 Calcasieu 33 Well .section, after Hopkins 33 Well section 62 Calhoun 82 Calyplraphorus trinodiferns 307 Camptoiiedes ( Ainusiuni) burlingtonensis 294 burling tonensis PI. 50, fig. 3, 294 Cancellaria quercollis PI- 54, fig- 3, 305 Cardiiiin alabatiietise PI- 50, fig. 4,294 uicoUetti 18 tuoiiieyi PI. 53, figs. 9, 10, 303 Index 341 Carpenter ijj Cassidaria brei'identata joy Cedar bluff 71 lick 61 Celastracecs 285 Celastrus taurinensis PI. 46, 285 veatchi Pl. 43, 285 Ceronia 304 Charlevoix 1 1 Cheftel's lake : 150 Chimney Rock, Winnfield, La PI. i, opp. p. 56 Cinnatnomum buchi PI. 43, 283 dubium 283 polymorphum 283 scheuchzeri PI- 41, 283 sezannense Pk 42, 283 spectabile 283 Claiborne Parish 88 Clays 127 Composition of 266 Effect of heat on 268 Fire shrinkage of 268 Origin of 265 Ph3'sical properties of 266 Physical tests of Louisiana satnples 272 samples, Report of Louisiana 264 Section at Chalk Hills 128 Section at Spring Ridge Church 128 Shrinkage 267 Slaking 27 1 Structure 265 Clear lake 159 Clendenin 43 Columbia 80 R. R. cut near PI. 6, opp. p. 8r Compass Needle, The , 312 surveying 313 Comparison of the Louisiana rock salt deposit to the great deposits of the world 261 Conrad 18 Coochie brake 79 limestone PI. 2 , opp. p. 57 limestone. Sketch map, ^-icinity of outcrop 59 timber PI. 3 , opp. p. 64 Co-operation with National surveys 7,8 342 Index. Cope 42 on Pleistocene Mammalia from Petite Anse, La 42 Corbula alabamensis 303 oniscus 18 Cornacece 286 Cornua auDiionis 17 Cornus studeri PI- 45> 286 Cote Blanche 230 Geology 230 Location and Topography 230 Section at Sea-Cliff 231 Cote Caroline 254 Geology 255 Location and Topography 254 Cottonwood bayou 156 Couley 79 Coushatta bluff 85 Section at 200 Cowhide and Horseshoe ]:)ayou 156 Coxe II Crassatella , sp 302 vadosa PI. 50, fig. 5, 295 Cretaceous fossils 292 outrops, 104 series. .■ 52, 62 Cross bayou 157 lake 158 bridge, Old shore line at 174 Delta at foot of PI, 15, opp. p. 168 Cross, Caddo and Ferr}- Lakes, Formation of 168 Cryptocarya eoligiiiiica PI • 42 , 283 Cryptogamia 279 Cyperites, sp PI- 32, 279 Cyprcea ludoviciana • 44 va iighan i 44 Dcedalc anibigiia , PI . 6 1 and 62, 337 Danville landing 93 Dap/iJiogetie longiqiia 283 kanii PI. 41, 284 sezannense 283 D'Arbonne 89 Darb}' 14 Delafield 15 Delta, foot (f Cross lake PI. 15, opp. p. 168 Formation of 174 Demeril 18 Index 343 Determination of meridian lines 8 Dickeson and Brown 20 Dicotyledo7ice 280 Dolet Hills 135 Doole^-'s baj'OLi 156 Drake 21 on gas theory of mud lumps 21 Drake's salt works '. 55, 121 Drift period 34 Dunbar 12 Duralde 13 Earliest geological work 11 Economic Geology 121 Edwards 36 Microscopic examination of New Orleans well material 36 ElcEOcarpus curopceus 2S6 Ellet 21 Elmer's ba^-ou 155 Engelhardt, Referred to 288 Gceppertia speciabilis 28.S Eocene, at Natchitoches 147 Series 63-93 EquHS 42 major 38 Ericacece 287 Exogyra costata 24 costata PI- 49, fig- i - 63, 292 FagacecB 280 Ferrj- lake 159 Ficus artocarpoides . PI. 35 , 281 harrisiana PI. 46, 281 lanceolata • . . 287 , 288 planicostata PI. 36, 282 Five Islands, The 62, 118, 125, 207 Age of salt deposits •. 260 described by Stoddard 13 Geographical position and general topographical features 219 Histor}' of the study of the Islands 213-219 Special report on. Contents 209-21 2 Fonies fomentariiis Pk 59, 336 Forshey 37 Fort Jessup 69 Fossil bones 17 plants 276 wood 3^ Fourth of July sprin g I47 344 Index Ffaxinus johnstrupi ? 1^1-44, 287 Fungi 332 Importance of stud}' 338 on garden vegetables 332 on forest trees 332 Wood-destroying 332 Fusoficitla jiivenis PI. 55, figs. 2, 3, 307 Fusiis harrisi .' PI. 52, fig. 7, 299 ludoviciana 44 Gabb 32 Galena 225 Gas well, Burning PI. 11, opp. p. 137 Geologic Pratique de la Louisiane, by Re}-niond Thomass}- 21 Geology of the Bottoms 1 75 of Hill-lands, Notes on 189 Georgetown 80 Gibbsland 85 Glencoe, Artesian well 258 W'ell section 258 Graham 15 Gra7ninecc , 279 Grand Cane , 73 Grande Cote. Archaeolog}- 234 Geolog}- 234 Cross section of PI. 30, opp. p. 241 History of mining operations 233 Location and Topography . . 232 Map of salt deposits PI. 29, opp. p. 241 salt shaft PI. 26, opp. p. 233 Topographic map of PI. 25, opp. p. 232 well sections PI. 27, opp. p. 233 well sections PI. 28, opp. p. 240 Grand Ecore 71 Grand Gulf 94 group 23 Origin of term 94 sandstone near Lena PL 8, opp. p. 96 Grandview bluflf 93 Gravel * 131 Gryphea convexa 292, 293 mutabilis 293 pitcheri 24, 63 Ihirsce 300 z'esictilaris PL 49, fig. 2, pi. 50, figs. 1,2, 292, 293 Gypsum 137 Hale's wood vard 202 Index ' 345 Haihiiiea graiidis 92 Hainiiietf s branch 85 Harlan 16 Harris, former work in northwest Louisiana 41 G. D 2S9, 311 Letter of transmission 6 Harrisonburg 130 Hayes 36 Haynesville 88 Hedera 281 auriculata 282 Helicina orhciulata 176 Hervej-'s canal 158 Heleroceras, sp PL 51 , fig. 4, 297 Hilgard 23, 107 " On the Geolog}' of the Delta and the INIud-lunips of the passes of the Mississippi. " 26 on the "Geology of Lower Louisiana and the Rock Salt of Petite Anse. " 27 History of Geological work in Louisiana 11 HolHck, Arthur 276 Homer 88 Hopkins (Prof. ) 29, 32 Humphreys and Abbott 22 Hydnuin septentrionale PI- 58, 335 Ice factory well 199 Ideal section across state, Hopkins 33 Ilex affiiiis Pi- 44, 285 gratidifolia 288 hibschi 285 longifolia 285 Importance of fossils 7 Indian relics at Cedar bluff 71 Inoceraniits bambini PI. 51, fig. 2. 295 Iron ore 132 Anah-ses of 133 Iron springs 148 Chemical analysis of 148 Jackson group, Hopkins 34 parish 82 stage 89 Jeaunerette well sections 257 Johnson, C. W 43 L. C 108 Jones 19 Jvidge Bry's comments on Geology of Northern Louisiana 16 346 Index Ju}::landacecc 280 Juf^lans dubia 280 occidetitalis 2S0 riigosa PI. 35, 280 Juglans schimperi Pi's 32, 33, 35, 280 Kansas City, Pittsburg and Gulf R. R., cut near Cross lake bridge.. . . 198 Kellia prima PI- 53. fig- 1 1 , 302 King's salt works 63 Kirkman's well 25 Knowlton 38 Lafayette 99 Features of formation in Ivouisiana 100 east of Mississippi 10 1 Origin of term 99 Lake Bristineau, Head of 55 Lake Charles 137 Lakes, formation of 163 LauracecB 2S3 Laiinis prunigenia ' PI. 41 , 284 primigenia 288 primeps 288 Laxispira linnhricalis PI. 51 , fig. 3, 296 Lead and Zinc 1 37 Leda acala 301 aldrichiana PI- 53, fig- 5, 301 corpulenioides 301 Leech neighborhood 76 Legtinien planulatum PI. 51 . fig. i , 296 Leidy 38 Leiosfoma ? ludoviciana PI. 52, fig. 8, 299 Lerch 39 Preliminary Report by 39 Leton , Section at 87 Letters of transmission 4-6 Levifusus indentns PI- 54, fig- 8, 72, 306 pagoda PI. 54, fig. 10, 306 supraplaniis PI. 54, fig. 9, 306 traheat aides 306 Liberty Hill ' 84 Lignite 134 Lignite described by Stoddard 14 Lignitic • 299 stage . 64 Lima pelagica PI. 49, fig- 5, 294 Limestone 130 Analysis of Winnfield 130 Index 347 Limestone concretions, Tertiary 131 in salt 227 near Coochie brake 59 Lincoln parish 82 Linearia metastriata PI. 50, fig. 7, 296 Lisbon 88 Loess, General Characteristics of 116 Origin of the 116 and Yellow loam, origin of terms 115 Lone Grave bluff 82 Lotus Landing, Wells at 180 Louisiana Oil Co's Well 25 Lower Claiborne 145 stage 73 Low''s creek 67 below Sabinetown , Texas 74 L 2icin(r 77 Lucina ozarkana 303 Lyell 19, 107 on the Delta and Alluvial 19 Mactra bistriata PI- 53. Ak- 4. 303 pnrtenitis 303 Magnetic Declination : 322 31agnoliace(P 282 Magnolia hilgardiana PI- 39. 282 lanceolata PI. 40, 282 longipetiolata 282 McGee 108 Mansfield 72 group 23 Section at 72 Many 136 Topographic map of ... PI. 4, opp. p 65 Vicinity of 68 Map making 7 Marl 137 Marthaville 71 Mastodon aniericanus 3'^ Mazzalina plena PI. 54, fig. 12, 306 Meridian lines, determination of 312 at Alexandria 322 at Colfax ■• 318 at Columbia 3^9 at Floyd 322 at Harrisonburg 320 348 Index Meridian lines, rietennination of at Mansfield 317 at Many 317 at Monroe 321 at Natchitoches 317 at Shreveport 320 at Winnfield 318 how established 314 need of . 314 Microscopical examination of New Orleans well material, Edwards. . . 36 Minden 87 Mineral prodncts, unimportant ' 132 resources 121 Mitra grantensis 44 Modiola alabamensis PI- 53. fig- 2, 300 stiibhsi n. sp . .n. 52, fig. 5, 6, 298 Monocotyledorice • 279 Monroe 82 Montgomery 91 Bluff at PI. 7, opp. p. 89 MoraceiT 281 Morton 17 Mounds, Origin of 192-194 Mud himps, Description of . . . . .• • 1 19 Theories of origin of 119-20 Mylodon 42 harlini ^ 38 My7-ica F lessigii 281 Nassa e.rilis PI. 55, fig. i , 307 Natchitoches . 70-77 area 141 Back lands 147 Front lands 146 Bluff on Cane river near PI- 13, opp- P- i45 parish 76 stratigraphy 144 topograph}- 141 township, Sketch of PI. 12, opp. p. 144 Natchez bluff as described b}- Lyell 20 Fossils near 20 Cydas 20 Cyclosto)iia 20 Heliiina 20 Helix 20 Horse 20 Lyniiuc . 20 Index 349 Mastodon 20 Megalonyx 20 Paludina 20 Physa 20 Planorbis 20 Pupa 20 Succinea 20 Stag 20 Natica alabamiensis PI. 55, fig. 9, 308 aperta PI. 55 , fig- !^, 308 etninula PI- 55, fig- 7, 308 Neithea qninquecostata PI. 49, figs. 6, 7, 294 New Orleans well material, microscopic examination, by Edwards. ... 36 Negreet, lower 74 ba^-ou .' 138 P. O. , Vicinity of 68 New Hope church 79 Nita Crevasse, The, Johnson 38 Northern Union and Claiborne 104 Nuttall 15 "Old salt works " 55 Old shore line at Cross lake bridge 174 Older Tertiarj^ The 195 OleacecE 287 Oligocene 93 Olla 92 Oniphalina friabilis 176 Ostrea crenuliniarginata PI. 52, fig. i , a, 297 falcata 293 falciforniis 77 {Alectryonia) larva 293 larva PI- 49- fig- 3, 293 plumosa PI. 49, fig. 4, 293 pulaskensis PI- 52, fig- 2, 3, 4, 198 thirscs ; 72 thirsts PI- 53, fig- I1 300 vesicularis 292 Orange sand formation 23 Orbitoides 32 niantelli 30, 34 Ouachita 92 Ouachita river gravel trains . . 104 Outlet ba3-ous, Formation of 161 Ovula sicbtruncata 44 Owen 19- 23 350 Index Pahnoxylon cellulosuvi 3^ quinstedti 38 Pascagoula fonnatioii, The 94 Peach Orcliard bayou 1 56 Pedetiiles 17 Pec ten burling tonetisis .... 294 cornuus 67 poulson i 32 quinquecostata 294 Pendleton 65 fossils 66 Persea speciosa PI. 41 , 284 Petite Anse 130 Archceology of 251 Cj-press stump section 250 Geology ; 243 History of mining Operations 239 Lakes 249 Location — Topography 237, 238 Marsh fires 249 Toprographic map of PI. 31, opp. p. 249 Section at new shaft 247 Vertebrate remains 245 Yearly production of salt 248 Petroleum and Gas 137 Phaneroganiia '. 279 Physiography of the Bottoms 181 Pholas alatoides PI. 53, fig. 1 2 , 304 Phos hilli , var. niagnocostattis 44 Pipe clay 24 Pinna 93, 300 Plagiostoma pelagica 294 pelagicuin 294 Plans of operation 7 Pleuroloina huppertzi 304 servatoidea 304 silicata .... PI. 54, fig. i , 304 siphns 69 PleurotoDiella vcatchi PI. 54, fig. 2, 305 Poacites, sp PI. 32, 279 Polygyra clausa 176 infleda 176 palliata / 1 76 thyroides 176 Polypodiacecr 279 Polyponts borealis PI- 56, 333 Index 351 Port Hudson bluff 12 fossils 1 14 group 23 Origin of term 1 1 1 Tbickness 114 Poston 's bayou 157 Potters clay 24 Poussin 16 Prairie Au Large, well section 258 Price's lick 55 salt works 123 Provencal 77 Pseudoliva sp 69 vetusta PI- 54, figs. 6, 7, 305 Pteris pseudopenncsformis PI. 32, 279 Pteridophyta 279 Ptyclwccras, near crassum PI- 51 , fig. 5, 297 Pyramidiila alternata 176 Ouaternar\- 107 , 146 formations of Louisiana, development and characteristics 109 phenomena 118 Ouerciis elcena 286 juglandina 287 niicrodentata PI. 34, 280 Radula pelagica 29A Raft, changes due to formation 167 Changes due to removal 171-173 Early attempts at removing 164-166 Effects of 167 Final removal 166-167 Growth and Decaj- of 161 Growth of vegetation on surface 164 Original extent 160 Origin 160 Rate of advance of head 162 Retreat of foot 163 The great 160 Rangia 12 Rattan P. O 9° Rayburn's salt works 52, 122 Fossils at 55 Map of . . 53 Red and Old Red bayous i55 Red land area 86 Red river 152 bottom basins i53 352 Index Bank Section, James Eric's place 175 slope 154 valley, Soil map of PI- M, opP- P- i53 wells below Shreveport, General section of 179 Width of channel 153 Reversal of drainage system 173 Redwine's spring 83 Rhavinacecc 286 Rhamnus cleburni PI- 47) 286 Ries, Heinrich 263 Road inquiry , Office of . 326 improvement S machinery 328 making bj- convict labor 326 Historical and technical papers on 326 monuments 327 No surveys made of 327 Notes on, by G. D. Harris 325 Objects of a road survey 327 Practical instruction 326 State aid 326 State laws 326 materials • 328 Robeline 7° Rock}- Spring church 63 Rosefield 93 Fossils at 93 Rostellaria vclala 29 Ruston, Nine miles west of 83 Sabine parish salt works 124 Sabinetown 67 Texas, Profile, bluff at 28 Salines of North Louisiana, discussed by Hilgard 23 described b}- Stoddard 13 Salix longa 287 Salt I2t, 226 Analyses of 227, 248 licks 66 Sands i99 and clays, colored 190 Sandstone varieties 129 Sandy soil, light I47 Sapindus angustifolius Pk 25, 286 Spotacece 287 Sapotacites americanus PI- 42, 287 Scale, illuminated 3^5 Index 353 Sediment of the Mississippi, The, by Dickesoii and Brown 20 Sedimentation 1 70 Sewell's canal 157 Shells from the front land 176 Shreveport 73, 136, 138 Delta near PI. 15, opp. p. 168 elevations 205 Location 152 Slaughter Pen bluff near PI. 18, opp. p. 200 Table of contents of S. area 149 Sigaratus declivus PI- 55, fig. 10, 308 Silver lake and Poston's lake, formation of 169 Sinipkin's place 75 Slaughter's creek lignite 66 Sodo lake 158 Soil maps ; 7 Soils, origin 1 78 Peculiarities and distribution of 177 varieties 177 Solarium bellcnse • Pk 55i fig- n. 308 Solsniya p/a>tii/ata 296 Sparta 84 Montgomerj' road, 24th mile stone 80 sands 43 Springs 147 Sterling and Irishman's bavou 156 St. Maurice 78 Bluff at PI. 5, opp. p. 73 and Montgomery 103 • Stoddard 13 Stone Coal bluff, vSabine river 66, 135 Stonewall 73 Storm}- point. Ferry lake 202 Stubbs, letter of transmission 4 Sulphur 1 26 City, Calcasieu parish 1 26 in mass PI. 10, opp. p. 129 mining PI. 9, opp. p. 128 Syke's Ferry 88 Talcott 19 Tancock's prairie 91 Terebratulina sp PI. 5 1 , fig. 7, 297 Test wells 7 Tetranthera prcecursonia PI. 44, 284 Thetis sp 295 354 Index Thoinassy 21 section of 258 ' ' Tomitclla ? bnllaia " 296 Totten, Joseph G., report of 19 Toxylon longipetiolatiini PI. 48, 282 Trametes pini PI. 60, 337 Transit, The, its use 312 Trezevent mound 202 Trigonia cufaulensis PI. 50, fig 9, 295 Trinity baj'ou ] 56 Tritonidea pachecoes PI- 54- fig- 1 1 > 306 Tullos 91 Turrilella huiiierosa PI- 55, fig- 5. 308 morloni PI. 52, fig. 9, PI. 55, fig. 4, 69, 299, 308 pauper 297 prcecimta PI. 55. fig- 6, 308 Uhnacece 280 UlniKS ieniiinervis PI. 32, 280 Upland falts, Age of 191 Vasherie branch 80 Vaughan on Stratigraph}- of Northwestern Louisiana 42 Veatch, A. C I49. 209 Veniella, sp 295 Venericardia planicosta, var PI. 53, fig. 6, 69, 93, 302 Vernon parish 1 29 Vicksburg group 23 Victoria Mills 76 Vienna §3 Vining Mills 82 Volutilithcs petrosHS. 69, 305 Waterfalls and Rapids, Formation of 182 Water supply 1 79 Wave-formed bluff PI- 17. opp. p. 176 Webster parish, Northern part 8? Well sections 19° Winnfield 79 limestone 5° ' ' marble ' ' quarry, v'^ketch of 57 Winn parish 7^ Wyant's Bluff 93 Yellow loam. The 116 Distribution of ■ ' 7 Yoldia aldric/iiana 3oi corpidentoides . . .' 3°! Yoiingblood mound 202 Zeuglodon bones found at Tullos 92 cetoides '9 •u UC SOUTHERN REGIONAL LIBRARY FACILITY A 000 632 884 3 U rc-' .J r ■V>-..-, . 6 a. 1210 00259 4735 C^