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POWELL DIRBCXOB ON HE CAMBRIAN FAUNAS OF NORTH AMERICA PRELIMINARY STUDIES BT CHARLES DOOLITTLE WALCOTT WASHINGTON aOVEKNMENT PRINTING OPPICB 1884 0^^2.c^.Vl I t3 Sir: iinry s TLo early p Hon. Depabtbient op the Interior, United States Geological Survey, W(MhingtOH D. C, July 1, 1884. Sir: Herewith I have the honor to transmit the first of mv nrelimi- nary studies on the Cambrian Faunas of North America Very respectfully, Hon. J. W. POWELL, '"^"''^^ °- '«'^"50TT. director U. 8. Oeologiml S«nwy. (288) 5 95<)0() I.— Let II.-Re\ c ril.— Fai IV.— On I r'LATR CONTENTS. , _ ^ P«ge. I. — Letter of transmittal 5 II.— Review of the fauna of the Saiut John formation, contained in the Hartt collection a ril.— Fauna of the Braintroe argillitea 43 I v.— On a new genus and species of Phyllopoda from the Middle Cambrian .... ttO I li LUST RATIONS. r-LATR I.— Fossils of the Saint John Formation 56 II. — Fossils of the Saint John Formation r,8 in.— Fossils of the Saint John Formation '. 60 IV.— Fossils of the Saint John Formation (52 v.— Fossils of the Saint John Formation 64 VI.— Fossils of the Saint John Formation 66 VII.— Fossils of the Braintree Argillites 68 VIII.— Fossils of the Braintree Argillites 70 IX.— Fossils of the Braintree Argillites 72 X.— New Phylloid crustacean 74 (287) T ON REV co: UN Du and t 'The Ooolofj }iailey, '2uil vd, tion. I think John, a Now Hi c'liaract tli« Pal to geolf The J. 1>. 5) IIH and reu tonis." h)cal na Saint well-kn< ing that Mr. \ Canada, that tho lying bo wick. ( iinportai advantaj that arc Lanrcuti I cann< original fihonld bi at Saint The na Braiutrei acters wl hrian, roi Heitaratei ON THE CAMBRIAN FAUNAS OF NORTH AMERICA. PREI.IMINAllY STUDIES. By Ohablkm 1). Walcott. REVIEW OF THE FATTNA OF THE SAINT JOHN FORMATION CONTAINED IN THE IIARTT COI^T^ECTION AT CORNELIj UNIVER8ITY.' During; tlie summer of 1877 the writer visited Saint Jobu, "^^ B., and taking advantage of information kindly given by Mr. G. F. Ai at- 'The tonn "Sftint John Gronp " was first propoHed in 1865 (Observation^ on the Ooolo^y of Houthorn Now limnswiok, Frederioton, N. B., pp. '26-32) by "* <■ i%n. L. W. JJailcy, G. F. Matthew, and C F. Hartt. Snbsequeutly, Mr. J. W. Dawson (Acad. G ol., 'inded., p. 638, 1868) prop< ><">'' asnbstituto the name Acadian for the same fm "na- tion. Ho nays: " This formation lias as yet boon known an the Saiut John Gr 'p; but I think this nauir ^suitable, both on acconntof the number of places known n-* Mnint John, and on account of the variety of formations occurring near Saint John, in Now Itriinswick, and would therefore propose for the group now under consideration, charactorizod by Paradoxides, Conocephatites, &c., and the oldest known member of tho Pahoo/oic of America, the name Aca) as " distingnished from all the neighboring parts of America by the enormons and remarkable development within it of rocks of the Carboniferous and Triassie sys- tems." This certainly renders the name inapplicable as a substitute for a well-defined local name previously given to the formation under consideration. 8aint John, N. U., is quite as well known as Trenton, New York, from which the well-known Tronton limestone is named. We would not give as a reason for chang- ing that name that other towns in the United States bear the name of Trenton. Mr. Matthew, in speaking of the Saint John formation, says (Trans. Roy. Soc. Canada, vol. i, p. 87, 1882): "From those reports and from the map it will be seen that tho strata of the Saint John Group All a number of narrow, trough-like basins lying between the Bay of Fundy and the central Carboniferous area of New Bruns- wick. Of these basins, that on which tho city of Saint John is situated is the most important, and it is here, also that the life of tho period can be studied to the best advantage. The Saint John basin lies diagonally across the ridges of Hurouian rock that are found in the eastern part of Saint John County ; and touches the ridge of Laureutian rocks that divides this county from Kings." I cannot but think that if we pay attention to the law of 'priority, justice to tho original discoverers of this group requires that the name of ^nint John formation Hhoidd be used as expressing tho division of the Lower Cambrian, so well developed at Saint John. The name Saint John or Acadian cannot well be applied to the Newfoundland or Braiutrec Paradoxides beds. The three localities present local differences and char- acters which, while permitting their being united under the general term Lower Cam- brian, render it necessary to use a local name for the formation in each of the widely- Hcparated localities. (289) 9 10 CAMBRIAN FAUNA OP NORTH AMERICA. [BULL. 10. thew, obtaiued a large collection of fossils from tbe typical localities at Saint Jobn, Ratcliff's Millstream, and Portland, from wbicb Mr. C. F. Hartt procured tLo collection described by bim in tbe second edition of Dawson's Acadian Geology. Subsequently wben working over tbe material, it was with great difficulty tbat more tban the com- mon species could be identified from tbe descri[)tions, and few figures given in tbe Acadian Geology. Tbe writer at tbat time formed the plan of illustrating the original typical Hartt collection and also the entire fauna, as far as possible. His own collection afterward went to the Museum of Comparative Zoology at Cambridge, Mass., and it was not until tbe latter part of 1883 tbat tbe trustees of Cornell University came in possession of tbe Hartt collection. Through tbe co-operation of Mr. H. S. Williams, paleontologist of the university, the loan of the col- lection was obtained for tbe purpose of illustrating tbe type specimens and such other material as would add to our knowledge of the faumi. In writing to Mr. L. W. Bailey, of Fredericton, iX. B., and Mr. G. F. Matthew, to secure their cooperation, the writer learned for the first time that Mr. Matthew was engaged on a monograph of tbe fauna of the Saint Jobn formation. The plan of illustrating tbe entire fauna was at once changed so as to include only the H..rtt collection, and Mr. M.atthew was requested to propose specific names for the new species with tbe exception of one form with wbicb tbe writer wished to connect the names of Mr. Hartt and Mr. Matthew, tbe two gentlemen who first gave to the scientific world a definite knowledge of this early Cambrian group. Mr. Matthew kindly accepted this proposal, and the writer proceeded with tbe work, using only the material contained in the Hartt collection. Mr. Matthew's valuable paper on tbe genus Paradoxides of tbe Saint John Group, has already appeared (Trans. Roy. Soc. Canada, vol. i, 1882), and from it we learn tbat be recognizes three well-defined species and six varieties: Paradoxides lamellatus, Hartt: P. lamellatus, var. ioWca i : be low down in tbe Menevian if not representative of that of portions of the Harlech and Longmynd gronps. Near Saint John, N. B., there is a commingling of representative species that are distributed in the St. David's section of Wales, from the Harlech to the Upper Menevian, a fact that tells us plainly that we need not look for a close similarity in the succession of individual species in sections of the same relative geologic position when widely separated. The physical conditions of environment and the geographic distribution of species tend to variation in the assemblage of forms at localities but slightly separated, and still more when widely distant from each other. In the Braintree argillites there are four species, Hyolithea Shaleri, Walcott (this bulletin), Paradoxides Harlani, Green (Amer. Journ. Sci., vol. XXV, p. 336, 1834), Ptychoparia Rogersi, Walcott (this bulletin), and Agraulos quadrangularis, Whitfield (Bull. Amer. Mus. Nat. Hist., vol. 1, p. 147, 1884). HyoUth€8 Shaleri is closely allied to Hyolithes excellem, Billings (Pal. Foss., vol. ii, pt. 1, p. 70, 1874). The Paradoxides Harlani is of the type of Paradoxides Bennetti, of Newfoundland, as found above the Saint John fauna, and corresponds to the Bohemian group of the genus typified by P. spinosus, Boeck, and the Menevian P. Hicksii, Salter. Agraulos quadrangularis, Whitfield, is a type present in the Paradoxides horizon in Newfoundland, as A. so- cialis, A. strenuus, and A. affinis, Billings (Pal. Foss., vol. ii, pt. 1, p. 71), in the Menevian of Wales, as A. longicephalus, Hicks (Quar. Jour. Geol. Soc, vol. xxviii, p. 170), in Bohemia, as A. ceticephaliis, Barrande (Syst. Sil. Bohfime., vol. i, p. 405). Ptychoparia Bogersi is more of the type of Ptychoparia Emmrichi, Barrande, of Bohemia. Up to the present time no other localities of the Paradoxides fauna have been discovered in North America. The relations of the Saint John fauna to the remaining portion of the Paradoxides fauna in Newfoundland we havo mentioned, but as yet no section has shown the connection of the Paradoxides fauna with that of the next superior or Georgian fauna. As I am engaged on a review of the latter fauna, the discussion will be omitted here to appear in a paper on that portion of the Cambrian fauna. Genus EOCYSTITES, Billings. EoOYSTiTES PRiM^vus, Billings. Plato i, fig. 2. Eocyatitea primcBvus, Billings, 1868, Acadian Geology, Dawson, 2d ed., p. 643. No description accompanies the illustration of the single plate of this form, and, in fact, little can be said of it from the oiiiterial in the col- lection* - (294) WALCOTT.J FAUNA OP THE SAINT JOHN FORMATION. 16 ides fauna The plates are polj'gonal in outline, variable in size and form, elevated at the center, and ornamented by 9, 10, or 11 principal ridges radiating from the center with smaller ridges coming in between the larger ones, usually showing a pentagonal arrangement. The plates vary from 3 to 5 millimeters in diameter. It is quite probable that a new generic form is indicated, but in its relations to other genera nothing can be de- termined. Protoeystitea Menevenais, Hicks, evidently belongs to a aim I ilar type, if not to the same genus. Formation and locality. — Cambrian. Saint John for/nation, Batcliff's I Millstream, N. B. , Genus LINGULA, Bruguiere. LiNGULA ? Dawso:si, Matthew. Plate -v-, flg. 8. Lingnlaf Dawsoni, Matthew, 1884. MSS. Shell small, broadly subellii>tical, subattenuate towards the beak; margins gradually expanding and curving from the beak to the center, where the shell has its greatest width, and thence narrowing towards the front, which is broadly rounded. General surface depressed con- vex, becoming more convex towards the beak. Surface marked by flue undulating concentric lines crossed by radi- ating lines that are seen only by the aid of a strong magnifying glass. In form this species approaches i/i/j//M/e//a/(?rr«ressed, with a shallow sinus running from the umbo to the front. Umbo not elevated above the liinge-area, which is very narrow, and marked by fine, parallel longitud- inal striie. Hinge-plate bearing two slight incurved internal processes. Ventral valve more arched than the dorsal, with a narrow, flat margin produced in the plane of the valve. Hinge-area triangular, concave, luul marked with tine parallel lines. Umbo elevated above liinge-line about one-fourth of length of shell. Foramen triangular and of moderate size. Surface ornamented by about thirty prominent rounded, radiat- ing plicsB, increasing iu width towards the margin, becoming less ele- vated and slightly curved toward the ears, crossed by a number of dis- tinctly marked, concentric, squamose lines of growth, and numerous flue concentric stria?. The radiating plica; increase by bifurcation, which takes place at about one-third the distance from the umbo to the margin." The figure accompanying the above description is that of a rather transverse ventral valve, on which the radiating costse are unusually strong. They also bifurcate in a manner observed in but one other specimen in the collection. At first sight this shell will be separated as a distinct species from the variety, having sharp, somewhat distant ribs radiating from the beak, with finer ribs appearing between them on the cast, but other specimens occur where the two surface chai^ters are shown on the same shell, aud give the im])ressiou that we have a single variable species, the two extremes of which are shown in our figures 1, Id, of plate i. The crowding together of the increased num- ber of ribs on the costate variety gives the bifurcating character to the ribs or costa). The ventral valve of 0. Billingsi is little elevated, in this respect be- ing unlike other Cambrian species, aud there does not appear to be any nearly-related species of Urthis in strata of Cambrian age. Orthis llwlisi, Salter (see Davidson's Mon. Brit. Foss. Brach., vol. iii, p. 230), is the prevailing form in the Menevian of Wales, and in some of (297) Bull. 10 2 V 1 V.l J.. 18 CAMBRIAN FAUNA OF NORTH AMERICA. [BULL. 10. its phases resembles 0. Billingai. Among the Swedish forms the latter mivy be compared with 0. exporecta, LioDarsson (Bihang till K. Svenska Vet. Akad. Handlingar. Band. 3, N:o. 12, p. 12, 1876). Formation and locality. — Cambrian. Saiut John formation, Batcliff's Millstream and Saint John, N. B. Obthis, sp. t Plate i, fig. lo. Associated with the preceding at Saint John, there is a bmall single dorsal (?) valve of a species of Orthis that appears to be distinct from O. BHUngsi. A moderately well-defined median sinus is shown and the surface, as preserved in the cast, was somewhat finely ribbed. Professor Hartt refers to a new species of Orthis as not being suffi- ciently well rei)re8ented to warrant its description, but gives another specimen, fig. Ic, plate i, as the form. This I consider as a variety of O, Billingni, and the shell under consideration may only have the same position when a larger series comes to be studied. m Genus HARTTIA, n. gen. This generic name is proposed for a unique little shell found in as- sociation with fragments of trilobites of the genera Paradoxides and Ptychoparia. Description. — A small, oval, patelliforni shell, having a low, broad ridge originating on the posterior (?) side of the interior that supports a subcordate shield-like expansion which extends out over the anterior (?) portion of the interior when we look down into the shell. The broad base of the ridge and the genersil character of the shield-like extension are well shown in the figure on plate i, fig. 3. The character of the apex s unknown, as the onlj^ representation of the genus and species is in tae form of a cast, showing the interior of the central portion and, around the margins, the cast of the apparently smootii outer surface. The interior ridge and shield-like expansion is of a peculiar character, and unlike that of any described recent or fossil form known to me. It is so well marked that there is little hesitancy in proposing a new genus for its reception. The genus may be included in the Oalyptraii- die nearest the genus Crepidula, if we compare the shield-like expan- sion with the shelf or shelly partition of Crepidula. However close or distant its relations to the latter, it certainly appears to be the rep- resentative of the Calyptrieida; type in the Cambrian, and adds another form, showing the ditterentiation of the invertebrate fauna in the old- est fauna yet known on the American continent. The generic name is in honor of Mr. O. F. Hartt. With it I wish to | (298) W.M.COTT.) FAUNA OF THK SAINT JOHN FORMATION. m associate that of Mr. G. F. Matthew, the discoverer of the Cambrian age of the Saiut Johu formation. HARTTIA MATTHEWI, II. 8p. Plato i, flg. 3. Tlie characters of this species have already been given under the description of the genus. The base of the shell, as shown in the 8pecini(3U, measures 2.5""» by 3.5'""'. It was probably a little larger, as the true margin is not to a certainty clearly shown. There is no reference or record number attached to the specimen, and nothing is said of it in Mr. Hartt/s notes as published by Mr. Dawson. A scratched outline around the specimen shows that it had been noticed, but whether by one of the collectors of the specimens or by Mr. Hartt is unknown. Formation and locality. — Cambrian. Saint John formation. The character of the slate and the embedded fossils is similar to that of the material from liatclitf 's Millstream, and it was associated in the collection with specimens from that locality. Genus PAL^ACMEA, H. & W. Pal^aomea ? AcADiCA, Hartt. Plate i, fig. 6. Discina Acadica, Hartt, 1808, Acadiau Goology, Dawson, 2d ed., p. 644, Fig. 222.. Description. — " Shell elliptical in outline; sides more or less straight. Conical, but very depressed. Apex apparently central. Surface marked with a number of deep, concentric, irregular, sharp furrows, not always continuous, and often breaking up into smaller grooves, and all these seem at times to be impressed with lighter lines running nearly parallel with them. Of the large furrows from nine to ten can nsnally be counted. The whole surface of the shell is marked with a great number of delicate raised lines radiating from the summit to the circumference, and just visible to the naked eye." An examination of several specimens of this species, including the tyi)C8, leads me to. think with Mr. E. P. Whitfield (Bull. Amer. Mus. Nat. Hist., vol. i, p. 141, 1884), that it is not a true Discina, but prob- ably a univalve shell, allied to Palajacmea or Stenotheca. The ma- terial in the collection is very poor and fragmentary ; so much so that the generic reference is to be considered as merely provisional. Formation and locality. — Cambrian. Saint John formation, Rat«litt''i^ [Millstream, N. B. (299) m ■ '. ■*■, i m ■I . **■■ \¥^ 20 CAMBRIAN FAUNA OF NORTH AMERICA. [BULL,ia GenuB HYOLITHES, Eichwald. Hyolithes Acadica, Hartt. Plate ii, flg. 5. t Theca Acadica, Ilartt. Label on Hpocimon. Forui an elongate triangular i)yranii(l, tapering gradually and uni- fornaly to an acute extremity. Transverse section subtriaugular, about twice as wide as high ; the lateral angles acute from comi)re8sicn in tbe specimens in tbe collection. Ventral face slightly arched; anterior margin extending forward in a semicircular subspatulate extension. Dorsal surface rather strongly convex. Aperture unknown, but un- doubtedly oblique, judging from the character of the extension of the ventral side. Operculum unknown. Surface of shell miirked by concentric lines of growth, parallel to the margin of tbe aperture, and exceedingly tine longitudinal strisB visible only by tbe aid of a strong magnifier. In general form this species approaches very closely to Hyolithes AmericanuK, Billings (Can. Nat. n. ser., vol. vi, p. 215, 1872), but tqually so to the Devonian If. aelia. Hall (Pal. N. Y., vol. v, pt. 2, p. 107,) exce])t in the more rounded dorsal side. Owing to the imperfect condition of preservation of the species illus- trated from the Menevian group of Wales, it is difficult to ibake com- parisons with them. Professor Ilartt's specific name is retained, as the probabilities are that the form is different from the American Potsdam and Georgian species, although allied to H. primordialis, Hall (Six- teenth Ann. Kep. State Cab. Nat. Hist., p. 135,* 1863), and also the Menevian forms of the genus in Wales. Formation and locality. — Cambrian. Saint John formation, Batclififs Millstream, N. B. Hyolithes Danianus, Matthews. Plate ii, figs. 7,7a, b. Hyolithes Danianus, MatthewH, ld84, MSS. Form that of an extremely elongate rounded subtriaugular pyramid that, in some examples, curves a little to one side as it becomes grad- ually attenuate towards the apex. Transverse section semielliptical ; moderately convex on the ventral side and still more so on the dorsal. Ventral face flattened and almost concave along the center, rounding up on each side to the somewhat rounder lateral angles. Dorsal face not very strongly convex transversely. Form of aperture unknown. Associated operculum broad oval, or subcircular in general form. The side corresponding to the ventral side of the shell curves regu- larly, but is not as convex as the opposite side. The umbo is* situated (300) WAIX;OTT.| FAUNA OF THE SAINT JOHN FORMATION. 91 about four-fifths the diHtauce from tho dorHul niargiu, and extendH laterally as a low, rounded rid^e towards the rounded angles formed by the union of the ventral and dorsal sides of the operculum ; just in front of these ridges a slight depression exists, also a depressed area back of the umbo, or towards the dorsal margin ; the inner side shows a Hharp ridge corresponding to the umbonal ridges on the outside, and also a sharp, short, elevated ridge between the ventral margin and the ]»osition of the umbo on the outer surface. The general bo«ly of the sliell of the o])erculum appears to have becMi (piite thin. Surface of the shell marked by transverse, concentric undulations of growth that arch slightly forward on the ventral side. Outer surface of the oi)erculum marked by fine concentric strise and very tine, some- wiiat obscure, radiating stria; ; inner surface with fine, slightly irregu- lar, radiating lines or stria;. There is considerable range of variation in the form of the shells of this species. In some the flattening of the ventral side is lost, and only a convex surface is shown, and the dorsal surface has a narrow longitudinal lino on each side of the center. The curvature of the shell also varies considerably. A number of specimens of the operculum are associated with the shells, but none were observed attached before the mouth of the shell. One unusually curved shell having a nearly round section, was la- beled Orthoceras 1 n. sp., by Professor Ilartt, as trac(;s of what ap- pear to be septa are shown. The distances between the septalike par- titions are unequal, and in other specimens this is seen to be owing to tlie filling of cracks across the tnbe. This species recalls ffyolithcH cinctua, Harrande (Syst. Sil. Boheme., vol. iii, plate ix, tigs. 8-12), and the form of the associated operculum is also similar. Formation and locality. — Cambrian. Saint John formation, EatcliflF's Millstream, N. B. Hyolithes Micmac, Matthew. Plate ii, fig. 6. j nyoUthea Micmac, Matthew, 1884, MSS. Form that of an extremely elongate, ronnded, subtriangular pyramid I tliat becomes gradually attenuate towards the apex. The true trans- verse section is not preserved, owing to the crushing down of the shell, I and appears to have been semielliptical or rounded subtriangular. Form of aperture and operculum unknown. Surface of the shell smooth externally ; the interior is marked by fine, [raised, longitudinal lines. In form this species is not unlike Hyolithes Danianus, but the smooth |outer surface and striated inner surface distinguishes it from that and ilso any other described species known to me. (301) ':-vm 99 CAMimiAN FAUNA OP NORTH AMKRICA. iniiM.10. It T)iii)enHinnR : Length of Ht)ociiii»ii 20""", width at tti»orturp 4'°">. Formation and locality.— CaiuhriAii. Saint John formation, aiiBo- oiated with Microdiscus punotatus at Uatcliff's MillHtreani, N. B. Genns AGN08TUS, Bronguiart. Agnostus Acadious, Hartt. Plate ii, flgH. 2, 2a-c. /IgnoBtua Acadicun, Hartt, 1808, Acncliaii Geology, Dawson, 2(1 ed., p. 655. A(jno»tii» aimilis, Hnrtt, 1868, Acadian Geology, DawHon,2d ed., p. 65(i. Description. — "Head minute, transversely-elliptical, or snbcircular ; breadth and length about equal, convex but very depressed, outlines in front and on the sides sliglitly straightened. A narrow, flattened, and but very slightly elevated border goes round the front and lateral margins. This is separated from rest of shield by a narrow, shallow, flat space, or groove, which, on going posteriorly along the lateral mar- gins, loses gradually in width toward the posterior angles of shield, which are rounded. Glabella a little less than two-thirds the length of | shield, long elliptical, depressed convex, but more elevated than other parts of the shield, about twice as long as broad, bounded anteriorly and laterally by a sharp, rather deep groove concentnc to the outer one above described. A well-marked transverse furrow, arching back- wards, separates the anterior third of the glabella as a subcircular lobe. Posterior part of glabella rounded, but impressed on each side by a lit- tle lobe situated in the angle between the cheek-lobe and the glabella. These little lobes are about one-quarter the size of the anterior glabellar I lobe. Cheeks of the same width throughout, and uniting in front of j the glabella, being bounded by the two concentric grooves above men- tioned. Posteriorly they are rounded ; in width they are rather greater I than the glabella. They are convex, more elevated along their inner margin, but sloping outward roundly and evenly. Glabella with its [ lobes project considerably beyond posterior margin. Surface smooth. Pygidium of this species (?) of abdut the same outline as cephalic shield. The posterior and lateral margins have a slight, raised border, separated from lateral lobes by a shallow but well-marked groove running par allel to the margin. This groove widens at the point where it bends to I go forward along the sides in such a way as to encroach on and thin out | the marginal fold, and, just before reaching the anterior margin, it nar- rows Itself from the inner side so as to cause the lateral lobes to widen somewhat anteriorly. These are narrow, flattened, about half as wide as the middle lobe, narrowing to a point just behind the middle lobe, where they do not unite. The medial lobe is about five-sixths of leugtL of pygidium, shield-shaped, flattened, convex, more elevated than the lateral lobe. Its anterior border is slightly concave in the middle. | The lateral angles are rounded, and the lobe is contracted a little an- (302) Microdiaeua Dc wAi.roTT.I FAUNA OP THE SAINT JOHN FORMATION. S9 t4>iiorIy. It is bouuded by two deep and well-uiarked fiirrowR, which join one another in the middle of the nnirginalfnrrow, forniinf; a pointed arch. Medial lobe projecting further forwards than the lateral ones. A little spine is situated on its mesial line about one-fourth its length fioni front. Surface smooth." Alter a careful study of all the specimens in the collection, fifteen in luiinbi'r, I am unable to make out sufficient difl'cronces between the form *lt>N<;ribud as A. AcadicuH and that given as A.nimilui, to ('tstablish two Hpocics. There is a certain range of variation in the specimens as {tointod out by Mr. Hartt, but that is so variable and owes its origin so largely to the condition of preservation of the various specimens that it is not evident that two species are typified. Agno8tun Acadicvs is a type of the genus that occurs in the Menevian of Wales, as A. Cambrensis, Hicks (Quart. Jour. Geol. Hoc, vol. xxvii, J). 4(M), 1871) ; in Norway, as A. brevifrons, Angelin (Pal. Scan., p. 0, lSo'2) ; in Bohemia as A. integer, Beyr. (Sil. Syst. BohCmie., vol. i, p. 900, 185;^) ; and in the American Potsdam horizon as^. JV>o», Hall & Whit- ttoUl (Geol. Expl. 40th Par., vol. iv, p. 229, 1877). Agnvatus interatriv- <««,. White (Expl. and Surv., West 100th Merid., vol. iv, p. 38), from the Cambrian of Utah, is an almost identical species, diit'ering princi- illy in the posterolateral angles of the pygidium. Formation and locality. — Cambrian, Sai it John formation. Saint John, xN.li. Genus MICRODISCUS, Emmons. MiOBODISCUS Z)AWSONI, Hartt. Plate ii, figs. 3, 3a. Microdiacut Dawaoni, Hartt, 1868. Acadian Geology, Dawson, 2d ed., p. 654. Description. — " Cephalic shield semi-lunar, with thickened border crossed by numerous grooves running perpendicularly to the circumfer- ence. Glabella convex, narrow, rounded in front, conical and pointed behind, projecting beyond posterior border, without furrows or occipital groove. Cheeks convex, no eyes, and no traces of sutures. Posterior angles of shield with backward projecting opines. Pygidium subtrian- gular, with curved outlines, rounded in front and behind ; middle lobe distinctly marked, and divided into six segments ; lateral lobe also di- vided, furnished with a narrow border." This is a beautiful little trilobite that is quite distinct from described species of the genus. There are but three specimens in the collection, and none show the head and pygidium united. Formation and locality. — Cambrian. Saint John formation, Batcliff 's Millstream, K B. ' - (303) *fl -r,A 24 CAMBRIAN FAUNA OP NORTH AMERICA. [bulu 10. y ii MiOEODiscus PTTNOTATUS, Salter. Plate ii, lig8. 1, la-0. Mkrodiscus punotatuii, Salter, 1864, Quart. Journ. Geol. Soc., vol. xx, p. 237, plate xiii, iig, 11. Mierodiacua j>uuctatu8, Wbiteaves, 1878, Amer. Journ. Sci., 3d ser., vol. xvi, p. 22f'. Microdigoua ptiloheUua, Hartt. Name proposed (No. 14) on list of fossils sent to Mr. J. W. Dawson. . Head semi-elliptical in outline, rather strongly convex, and bordered on the front and sides by a depressed furrow and raised rim, the furrow containing numerous short furrows perpendicular to the margin, as ir. M. Dawsoni, but not as strongly marked. The posterior border is strong back of the cheeks, and has the furrow continuing from the sides ; a very narrow rim extends back of the glabella ; eyes and facial suture entirely absent. Glabella elongate conical, extending ba( kward in a strong spine as long as the glabella in medium-sized specimens and nearly as broad at the base. In some examples the spine is shorter and smaller. The glabella rises above the level of the cheeks and is about three-fifths the length of the head, bordered by strong dorsal furrows that are connected in front by a straight furrow with the depressed groove within the anterior mar- ginal border, perceptibly marked by two pairs of oblique glabellar fur- rows in some examples. Cheeks convex, prominent, strongly defined by the dorsal and marginal furrows. Thorax unknown. The pygidium, associated with the head of this species in great num- bers, has the same general outline as the head. The narrow marginal rim is well defined all around, w idest at the sides ; anterior marginal furrow very distinct; median lobe elongate-conical, extending back uearly to the marginal groove ; nine anchylosed segments are indicated by eight rather strong transverse furrows ; lateral lobes strongly convex, no furrow appearing back of the anterior marginal groove. Surface finely punctate, the punctae being rather large as compared with the depth. Dimensions of a rather broad head: Length, exclusive of spine, 3.5"""; breadth, 5"""; occipital spine, 3"""; pygidium, length, 3.75"'", breadth, 5""". This is an abundant and well-marked species. Mr. Hartt evidently intended to describe it, as the name is given in his list, and selected specimens were mounted on blocks, one of which bears the name Eodisous pulchellus, Hartt, n. g., n. sp. There is considerable variation ii; tho relative proportion of the length and breadth of the head, also of the pygidium in difl^e^ent specimens, owing to an original variation, and also distortion from compression in the shales. Mr. Whiteaves states that this species was first detected in the (304) WALCOTT.) FAUNA OF THE SAINT JOHN FORMATION. 25 Primordial slates of Saint Jo!it),*N. B., by the late Mr. E. Billings. It has since b^en observed in rocks of the same age on the Kenuebecasis Kiver, N. B., where it was collected by Mr. G. F. Matthew. The pygidium is very sinxilar U that of Microdiscus speciosun, Ford (Amer. Jour. Sci., vol. vi, p. 137, 1873). In comparing with the flgnres of M. pnnctatus given by Mr. Salter, it, is observed that the nuchal spine of M. punctatus is longer and more slender, and the su^iace of the cephalic shield and pygidium are pi ic- tate, whereas, in the Saint John's specimens, the surface is smooth, in event of the two forms proving distinct on a comparison of specime^is, 1 i)ropose that Mr. Hartt's name, M. pxiMiellus, be given to the American species. Formation, and localities. — Cambrian. Saint John formation, Katclifl's Millstream, N. B., and Manuel's Brook, near Conception Bay, New- foundland. Genns PARADOXIDES, Brougniart. Pabadoxides lamellatus, Hartt. Plato iii, fi};8. 2, 2a. ParadoxideB lamellatus, Ilartt, 1868, Acadiuu Geology, Dawson, 2d cd., p. G56. I'arudoxides lamellatus, var. loricatus, Mattliew, 1882, Traus. Roy, Soc. Canada, p. lO.'i. plate ix, fig. 19. Description. — "This is a small species distinguished from several others found with it by the presence of a number of sharp perpendic- ular laminae on the anterior lobe of the glabella." The types of this species consist of the casts of portions of two heads, both of which are illustrated on plate iii. It is, as stated by Mr. Hartt, distinguished from the associated species by the sharp perpendicular liimin?e or ridges in front of the glabella. Mr. Matthew has indicated a variety as i*. lamelatvs, var. loricatus. Tlie elevated ridges on the front of glabell:' are variable in the two type siwcimens, and I should not consider the v riation cited by Mr. Matthew as of sutiicient importance to establish a varietal name, especially as he suggests the idea that the transverse ridges or interrui>ted elevated lines owe their origin to the condensaticn of the front id area by transfer to the glabella ; this would necessarily induce a great variation in the form and arrangement of the elevated lines in relation to eacli other, although they might retain their general relation to the frontal margin. Formation and locality. — Cambrian. Saint John formation, Portland, a little northward of Saint John, N. B. Paradoxides Acadicus, Matthew. . Plate iii, fig. :?, :Jeariiig in the glabella, fixed cheeks, and the anterior lateral limbs. From our experience with the varying forms of Olenellus from Nevada, we should .scarcely consider these, on the evidence given, as more than varieties of one species, as Mr. Matthew has done. A num- ber of specimens of this species occur in the collection. One head (sp.?) indicates a trilobite IS"*", or 20"'". in length when entire, the portion of the head remaining beibg 0"°'. long. I'^or the purpose of illustrating the species of the Saint John fauna, luiown to me at present, several figures of P. Eteminicus are copied from Mr. Matthew's paper. Formation and localities. — Cambrian. Saint John formation, Portland and Itatclitf 's Millstream, N. B. (307) vi ■' -ti p ifc- iS? CAMBRIAN FAUNA OF NORTH AMERICA. fBULUlo. Genus CONOCORYPHE, Corda.3 CoNOCORYPHE (Subgenus?) Matthewi. Plate iv, figs. 1, la, h. Conocephalites Matthmci, llartt, 1808, Actiiliaii Geology, Dawson, 2(1 ed., p. 646. Conooephalifes gemini-spinosus, Hartt, 1868, Acadian Geology, Dawson, 2d ed., p. 653. Description. — " Head semicircular to seini-elliptical, more than twice as wide as long; front and lateral margins forming a regular curve; posterior margin nearly straight; posterior angles of shield flattened and rounded without spines; margin with a strong, round, rather narrow fold, which becomes narrower and lower towards the posterior angle of shield, where it disappears. This is separated from the cheek-lobes by a very deep, moderately-broad groove. This groove is arched forward in front by a large, semi-globose swelling, situated just in advance of the glabella, encroaching upon the marginal fold, causing it to be the thickest on each side of this prominence. "The posterior margin is also folded, but the plait io more or less in- clined backwards. The fold is narrow near the occipital ring, but grows more prominent and gains in width towards the posterior angle, but, like the anterior fold, it disappears at that point. Its course is not straight; at about half ihe distance of the outer angle it bends slightly backwards and downwards and then forwards slightly to disappear on the flattened or rounded angle of the shield. This fold is separated from the cheek-lobes by a groove shallower and broader than the mar- ginal one, which it resembles, by expanding gradually into the flattened space of the outer angle. This groove follows a course parallel to the fold which it accomiianies. Length from occipital furrow, about half that of head. " Glabella subconical, longer than wide, strongly rounded in front, and about half as wide anteriorly as posteriorly ; length about that of whole shield, strongly convex, but less elevated than the check lobes, bounded laterally and anteriorly by deep grooves, the anterior being not so deep as the posterior. Tbe sides of the glabella are impressed and divided into lobes by three pairs of deep lateral glabellar furrows. Those of the posterior pair are the longer and more deeply impressed. These furrows begin abruptly at a point somewhat in advance of the middle of the longer diameter of the glabella, and directed backwards at an angle of about 45° to the anteroposterior diameter of the shield, dis- appear abruptly without gaining the medial line, usually extending a little more than the third of the distance across the glabella. Those of the median pair begin also on the bounding groove very abruptly, only a little in advance of the posterior pair, but they are usually not so oblique, and extend on each side not more than a quarter of the dis- tance across the glabella. The distance between the outer extremity of ''See note on thia genus under remarks on tbe genus Ptychoparia. (308) WALCOTT.] FAUNA OV THE SAINT JOHN FORMATION. the median and anterior furrows is somewhat less than between those of the median and posterior, and these buii slightly impress the sides of the glabella, and occasionally are scarcely visible. The anterior lobe is about as widt as the one which follows it. "The occipital furrow is deeply cut in the outer third of its length and strongly directed forwards ; in the middle third it is not so deep and is quite strongly arched forwards. The occipital ring is narrow, strongly convex, and vertically arched, the sides being more or less narrowed, turned downwards and forwards, being projected obliquely more or less across the posterior marginal cheeii-groove towards the inner posterior angle of cheek-lobe. The ring projects backwards beyond the margin, but not beyond the posterior lateral angle of shield. The middle part is produced into a very short conical tubercle-like spine, directed slightly backwards. The cheek-lobes are strongly gibbous, and very regularly arched, the convexity being stronger anteriorly. A narrow, distinct, wavy ocular ridge begins on the cheek-lobe, just opposite the anterior part of glabella, and, thinning gradually out and arching, at first slightly forwards, curves round and is directed towards the outer angle of cheek- lobe, but it usually vanishes before reaching that point. From its an- terior outer side it throws ott" a very numerous set of fine, bifurcating, raised lines of ridges. These linesare directed outward from the primary line at a rather acute angle, and appear to bifurcate several times. This ocular ridge is thickened at its commencement, but is not so strongly marked at that point as in C. Baileyi. It is also more arched forward than in the latter species. The whole outer surface of the shield is covered by innumerable, close-set, raised points or granulations, just visible to the naked eye, but very distinct under the lens, appearing in the impression of the shield as minute punctures. These appear to be more distinct on the convex portions of the shield. The raised margins, cheek-lobes, glabella, occipital ring, as well as the lobe just in advance of the glabella, bear sparsely-sown, minute, short spines, which give to the surface a distinct granular appearance. These are always wanting iu the furrows and on the cheek-lobes, are more crowded on the outer halves of the cheek-lobes. They are true spines, but usually appear as granulations on the casts. " In very young specimens, a line in diameter, the shield is semicircu- hir, the cheek-lobes are extremely gibbous, and very much more convex than the glabella, and the preglabellar lobe is vei'y conspicuous." The above description gives all the characters of the adult head of this species as shown in the specimens contained in the Uarct collection. A number of small heads show embryonic features, but as Mr. Hartt did not describe these and Mr. Matthew is at work on the species and its stages of development, we will await the appearance of his paper. Mr. Linnarsson unites Conocoryphe coronatux, Barr. (Syst. Sil. de Boheme., vol. i, p. 424, plate xiii, tigs. 20-20), C. exxidanit^ Linnarsson (Sv. Geol. Unders. Afh., Ser. C, N:o. 35, p. 17, 1879), C. solvcnsis, (309) '»■•, ^f^>r{J! 'He, p. CAMBRIAN FAUNA OP NORTH AMERICA. [BULL. 10. \l- \9 I .' ti Hicks (Qnar. Jour. Geol. Soc, vol. xxvii, p. 400, plate xvi, flg. 8, 1871) and 0. Matthewi, Hartt, as a natural group chiefly characterized by the boss or elevation in front of the glabella. He speaks of C. (Elyx) laticeps, Attg. (Pal. Scan., t. 5, figs. 2-3, 1854), as the nearest allied from among Swedish species, and there appears tc be good reason for placing it very close to, if not in the G. coronatus group. Mr. Corda proposed the generic name Ctenocephalus (Prodrom. Mon. bohm. Trilobiten,p. 142) for this type of theOonocephalidae, and in many respects it is a convenient subgeneric terra. I know of no American species from the Potsdam or Georgian hori- zons that will fall within the group, although a species from the Georgian horizon, in Central Nevada, Ptychoparia Linnarsaoni, Walcott (Pal. Eureka Uist., in press), has a boss in front of the glabella much the same as that in C coronatus. The presence of large, free cheeks, well marked eyes, and facial sutures, places the species in the second division of the Conocephalidae under the genus Ptychoporia, or a sub- genus of the latter. Mr. Hartt describes a second species of this group under the name Conocephalites gemminispinosus, as follows : " Resembles C. Matthewi, but with wider and less elevated marginal folds ; clieek-lobes much more gibbous and semi-ovoid, &c., sparsely sown with minute spines, grouped two and two. Rare, at Saint John." This species does not ap- pear on the list of numbered specimens, and I fail to find any specimens that differ from the typical forms of C. Matthewi sufl3ciently to warrant a separate specific name. Under the circumstances it appears best to place the name as a synonym of C. Matthewi, on the grounds of imper- fect description, no illustration, no labeled type specimen, or a form iu the collection that can be recognized as the one referred to oy the author. Specimen No. 91 is referred to as G. Matthewi var. ?. This is a well-marked variety in its surface characters, as the scattered tuber- cles of C. Mattheici are crowded together and give the glabella, cheeks, frontal lobe, and margins a granulated appearance quite unlike C. Matthewi. The ocular-like ridges are also lost iu the crowding together of the tubercles; flg. 1 b., pi. iv. Formation and localities. — Cambrian. Saint John formation, Ratclift''8 Millstream, Saint John and Portland, N. B. The variety (= granulata) is labeled Cold Brook (= Portland, on authority of Mr. Matthew). CONOCORYPHE Walcotti, Matthew. "n a letter received from Mr. G. F. Matthew May 22, 1884, written „]nce the preparjition of this paper, he states that he has found a spi ies of Conocoryphe in the Saint John formation, characterized by trausverse bars on the glabella, a granulated but not tuberculated sur- face, and other features separating it from the other species of tho genus. For this species he proposed the name Gonocoryphe Walcotti m (310) WALCOTT.] FAUNA OP THE SAINT JOHN FORMATION. 01 a ])aper "On the ConocorypbidsB of the Saint John group, with remarks on Paradoxides," read before the Royal Society of Canada, May, 1884. Subgenus SALTERIA, n. subgen. Dr, Henry Hicks, in his description of Erinnys venulosn, refers the species to Salter (Brit. Assoc. Rep., 1865), where we find the name used and the relations of the genus to Harpides pointed out, and the fact stated that it has a great number of free segments and no facial sutures and probably no eyes. The description of Erinnys venulosa (Quart. Jour. Geol. Soc, vol. xxviii, p. 177), is of the type specfes, and gives that of the genus as far as known. Description. — " Ovate in form, being widest in front, and surface de- pressed. The largest specimens indicate a fossil at least 3^ inches long. <' Head semicircular, margined all round, but with no posterior spines wider than the body. Glabella small, occupying only about two-thirds of the length and about one-fifth of the width of the head ; pyramidal iu shape, slightly raised, and indented by three pairs of furrows, the hinder ones i eaching backwards nearly to the neck-lobe, and marking ofl" triangular lobes on each side. '' There are no distinctly-marked eyes or facial sutures, but a tolera- bly strongly -raised ridge strikes off on each side from opposite the upper ghibellar lobes towards the posterior angles, reaching nearly two-thirds of the distance across. From these ridges lines strike off in each direc- tion, especially forwards, dividing and subdividing in their course and giving a veined character to the whole surface. " Thorax composed of 24 rings ; axis narrow, convex, and tapering towards the tail ; plearfe compressed, grooved, and, including the spines, more than twice as long as the rings of the axis ; spines bent backwards from the fulcrum, at which part the surface becomes suddenly raised into a sharp, transverse ridge. " The tail is semicircular, and has a tolerably strong axis, composed of four segments. The lateral lobes are marked by four moderately well-defined ribs." This is certainly a very remarkable form, and is, as stated by Mr. Salter, related to Harpides ; still it does not appear to be congeneric with it. The first generic use of the name Erinnys of which we have record, was by Mr. Schrank (Faun. Boica, vol. ii. p^. 1, p. 152, 1801), for a genus of Lepidoptera. Mr. Schrank spelled the name " Erynnis." Mr. Agassiz suggested in his Nomenclator Zoiilogicus, 1846, that it be changed to Erinnys. The name was again used by Mr. J. Thompson (Arch. Ent., vol. i, 1857) for a genus of Coleoptera. In 1865 Mr. Salter proiiosed it for the genus under consideration, and in 1867 it was again proposed for a genus of Coleoptera by Mr. Oustalet (Scudder Index Univer., p. 115). As Mr. Salter's name was anticipated, it becomes (311) ".'^l - f( ,t 32 CAMBRIAN FAUNA OF NORTH AMERICA. [BULL. 10. i necessary to replace it, and the name Salteria is proposed in honor of the distinguished paleontologist. The generic description, as far as known, is essentially that of Salteria venulom. With it we may place 8. Baileyi, as it is an almost identical species, as far as can be deter- mined from the head and pygidium. CONOCORYPHE (SALTERIA) BAILEYI, Hartt. Plate iv, figs. 3, 3a ; pi. v, tigs. 7, 7a. • Conocephalites Baileyi, Hartt, 1868, Acadian Geology, Dawson, 2d cd., p. 645. Description. — "Head transversely semi-elliptical, half as long as wide; anterior margin in front more or less straight ; posterior margin quite straight ; posterior angles of cheeks slightly rounded and unfurnished with spines; facial suture never visible ; anterior margin of shield with a narrow, very elevated border, which is widest and most elevated iu front, and grows narrower and lower posteriorly, becoming obsolete, or nearly so, at the posterior angle of the shield. This border is separated from the other part of the shield by a deep, rather wide furrow, whicli is deepest in front, but grows shallower as the anterior border loses in height going posteriorly. General form of shield convex, but much depressed ; glabella more depressed than the cheek, subtriangular, de- pressed convex, broadly rounded in front, and separated from the cheeks and front by a deep, well-marked furrow ; width at base equal to length, which last is about seven-tenths that of shield ; very much narrowed in front. Lateral bounding furrows inclined to one another at such an angle as would cause them to meet if produced to the middle of the front margin of head. Occipital furrow deep and well marked, slightly arched forward in middle, and curving downward and forward, growing narrower at the extremities, and less deeply cut than the bounding furrow of the glabella. No lateral glabellar furrows, or very slightly marked, ever seen on casts. Occipital ring more elevated and rather wider in the center; bent forward at the sides; narrow, with a very low, spine-like tubercle in the center. Posterior furrow moderately deep and wide. Sides of shield bent slightly downward. Posterior angles flattened. Cheeks subtriangular, bounded by the straight dor- sal furrow, the straight groo^'^e which separates them from the glabella and the curved marginal furrow. They are more convex or gibbous than the glabella, sloping gently toward the marginal furrow, but steeply to the other bounding grooves. In the cast they are marked on the edge of the bounding groove of the glabella .at the i)oints where the straight sides of the latter begin to curve around the front by two small, low, but well-marked ocular prominences, from each of which extends a slight ocular ridge, with a more or less outward curve toward the | posterior angle of the shield, but usually loosing itself at about half the distance in a system of delicate ramifications, which may often be traced to the posterior angles of the cheek lobes. Like ramifications are thrown (312) WALCOTT.] FAUNA OF THE SAINT JOHN FORMATION. 88 off for the whole leugth of the ridge from its auterior side, .lud these occupy the surface of the cheek lobes in fronf of the line. The surface of tiie cast sometimes appears granular, but the mould is always smooth, luid the outer surface of the shield was unfurnished with tubercular or jjraiuilar ornamentation. The posterior border on each side of glabella is very elevated in the middle, and loses height thence each way. Cei)halic shield sometimes an inch and a half in width." On one specimen referred to this species the left posterolateral angle of tlie head shows a short, slender, rounded spine, a feature not men- tioned in the original description, and a short facial suture cuts ott' a slender strip of the postero-lateral side of the cheek, carrying the spine witL it. Tlie resemblance between the head of this species and that of G. (^(, ria) venulosa is very striking, the greatest difference appearing in the presence of a suf^ure line and postero-lateral si)ine. I suspect, how- ever, that, as in the case with C. {S.) Baileyi, the free cheek and spine arc broken away in C. {S.) venulosa, and have not been observed, owing to that. One specimen of C. [S.) Baileyi preserves twelve segments of the thoi-ax and the pygidium. The latter is of the type of that of C. {S.) venulosa, but the thoracic segments vary considerably at the genal an- gle of the pleural lobes and in the rounded instead of falcate termina- tions of the pleurae. The true number of segments in the thorax is unknown. Formation and locality. — Cambrian. Saint John formation. Rat- cliff's Millstream, 'jS. B. CONOCORYPHE ELEGANS, Hartt. Plate iv, figs. 2, i-'n, h. ConocephaUles elegans, Hartt, 1868, Acadian Geology, Dawson, 2(1 ed., p. 650. Description. — "Head or cephalic shield semi-circular or semi-elliptical, more than twice as broad as long, nearly straight behind; auterior bor- der with a very strong fold, separated from the rest of the head by a deep groove. This fold is widest and most elevated just in front of the glabella, where it is sometimes the tenth of an inch in width. At this point the groove bends abruptly and angularly, and arches forward on each side so as to encroach on the marginal fold and cause it to disap- pear at about half the distance between the middle point in front and the posterior angles of shield. The posterior marginal folds are very thin, most elevated in the middle, and sloping each way towards the occipital ring and posterior angles of shield. The axis of the outward half is more and more inclined backward from the perpendicular towards the posterior angles, which are rounded, more or less flattened, and with out backward projecting spines. The grooves separating the posterior fold from the cheeks are very deep, and are slightly directed forward. Length of glabella about sixth-tenths of anteroposterior diameter of (313) Bull. 10 3 ■ - --ii #1 .& ' 'hi r \^ • ■1* ■> » t M If ^ It" 34 CAMBBIAN FAUNA OF NORTH AMEBICA. (BULL. 10. WAU'orr shield, a little wider at base thau long, and less than half as wide an- teriorly; triangular, with anterior part rather broadly rounded, highly inflated, and bounded by deep grooves, which in front join in with the anterior marginal groove. There are three pairs of glabellar furrows. Those of the posterior pair impress deeply the sides of the glabella, are strongly curved backwards, aad scarcely reach a third of the distance across each side. The second and third pairs only just impress in like manner the sides of the glabella. Those of the second pair are curved backward, and extend about a quarter of the distance across the glabella. Those of the third pair are very short, and appear to be parallel with the transverse diameter, but they are not always distinct. Occipital furrow art of the shield is ornamented by very line, close-set granulations, distinctly visible to the naked eye, and by a set of delicate little tubercles more sparsely sown.!' This distinct and finely ornamented species may be compared with Conocoryphe bufo, Hicks (Quart. Journ. Geol. Soc, vol. xxv, p. 52, 1869). In the form of the head, frontal margin, and glabella, the character of the granulose surface and absence of facial sutures and eyes, as far as known, they are very much alike. We know of the presence of the pos- tero-lateral spines of the head in C. elegans, but not the occipital spine in C. bufo which is present in C, elegans. Conocoryphe Dalmani, Angelin (Pal. Scan., p. 63, pi. xxxiii, fig. 16, 1854), belongs to the same group of species and is very closely related to them. Liunarsson speaks of C tenuicincta, Linn., C. emarginata., Linn., C Dalmani^ and C. hufo as forming a natural group (Sv. Geol. Unders. Afh., 8e. C. N:o. 35, p. 20, 1879), and with these we add C. elegans^ as it is a similar type .and nearly identical with C. hufo and C. Dalmani. , Formation and locality. — Cambrian. Saint John formation, Batcliff's Millstream, N. B. Genus PTYCHOPAEIA, Corda. Ptychoparia Corda, 1847, Prodrom. Mou. boliin. Trilobiten, p. 141, Abh, den K. Bohm. Gesella. den Wissonschaften. = Conocephalus Zeuker, 1833 (in parte); Solenopleura, Augcliu, 1851 (iu parte); Crepiccphalus, Owen, 1852 (in parte) ; Conocephalites, Barraudo, 1852 (in parte). In looking up the history of the generic names Conocephalus, Cono- coryphe, Ptychoparia, and Conocephalites, we find that Conocephalus was first proposed by Mr. Zenker in 1833, with C. Sulzeri as the type, a trilobite without eyes and having a peculiar direction to the facial sutures of the head. (314) WALCOIT. FAUNA OF THK SAINT JOHN FORMATION. 35 In 1839 Mr. Eiimirich doacribed, an a diHtiiict species from C. SuJzeri, ConoccphulvH striatun, rel'erriiiff it (o the same genus, although it bns \vell-(U'Veh)j)ed eyes ami a direction of the lucial sutures ludike that of C. Siihcri. Mr. Corda, in 1H47, observed that C. Suheri and C./hiilus had been preoccw- l)ie(l tor a genus- of insects in 1812, lio i)roposed two generic names for the two types, Conocoryphe being given to G. Sulzeri and Ptychoparia to C. Htrialus. This division appears to me to be one dem.auded by the cliaracters of the two types, and I fully indorse the opinion of the late Mr. ¥. li. Meek (Sixth Ann. Kep. U. S. Geol. Surv. Terr. 1872, p. 487), tiiat Mr. Corda's names should be adopted and the subsequent name, Couocephalites, proposed by Mr. Barrande in 1852, treated as a syn- onym. Mr. Corda used the same type species in proposing the genus Conocoryphe, and there does not appear to be sufficient reason for refusing to adopt the name. Of the value of the genus Ptychoparia paleontologists may differ, but if we unite before our minds the char- acters of Ptychoparia striata and P. Emmrichi, the tyi)es referred to by Mr. Corda, and then bring together the group represented by Conocoryphe Suteri, G. coronatua, C. exsuJans, Linnnrsson, G. solvensia, Hicks, and C. Matthetci, Hartt, in the same manner, we will observe differences that, to me, appear to be of undoubted generic value. This division may be carried still further if we adopt Mr. Corda's third division of Cono- cephalus, Ctenocephalus, as a subgenus of Conocoryphe, and place C. coronatus, G. Matthewi, C. exsulamt, and allied species under it. From Mr. G. F. Matthew's study of G. Matthewi I am very much inclined to adopt Ctenocephalus in that manner. Mr. Meek (loc. cit.) thinks that in adopting this view the generic name Ptychoparia will necessarily be applied to nearly all the species of the Conocephalidsf described from American rocks. With some con- siderable exception this is true, and especially so of the group placed under the generic name of Crepice})hahis, by Messrs. Hall and Whit- field (Geol. Expl. Fortieth Par., vol. iv, p. 209, 1877). They revived the genus w hich was proposed by Mr. Owen (Geol. Surv. Iowa, Wis., and Minn., p. 576), making C. Haguei the first species. For the purpose of i)lacing before all the means of comparing the types of the two genera, they are figured side bj' side on plate v. Ptychoparia striatus, the type of the genus, has two more segments in the thorax than P. Haguei, but that is not a character of generic value of itself. Of Mr. Owen's type of the genus Crepicephalus, G. loicensis, only the head is known, although the pygidium usually associated with the head is peculiar and might give rise to a subgeneric group, but not as defined by Mr. Owen or Messrs. Hall and Whitfield. Ptychoparia Emmrichi, Barr. (Syst. Silur de Boheme. 1, p. 428, plate ii. Figs. 2-U), the second species arranged under the genus by Mr. Corda, diifei's in having the central portion of th ' head between the sutures in (315) \XA ;i <, I 1 86 CAMBRIAN FAUNA OF NORTH AMERICA. (BULL. 10. i =1 i front of the eyes narrower tlian in /'. striata, a feature quite prominent in the specieHfrom the Potsdiuu group in Wisconsin, etc. The pygidium is also more like that of P. Hnffuei, an«l the pleura have less angular ex- tremities. If the student ^vill compare hg. 4, i)hite ii (Syst. Silur. de Bo- hdmo, vol. i, 1852), P. Emmrkhi, witli llg. 7 of plate xiii of the same work, I think that he will scarcely wish to place the two species in two subgeneric groups. If not, there appears to he no other way but to place Crepicephalus as a synonym of Ptychoparia for all species except P. {CrcpivephaluH) lowemis, where it may be used as a subgenus on account of the peculiar pygidiunt. The genus Loganellus 1 )evine (Geol. Canada, Pal. Foss., vol. i, p. 200), is of the same type as Ptychoparia tJmmriohi, and is considered by Messrs. Hall and VVhittield as identical with Ore- ciphalus = Ptychoparia Hayuti. Solenopleura Angeliu (Pal. Scan., ]>. 26) and Liostracus Angeliu each ajiproach this group. Liostracus rep- resents the forms with the glabella devoid of furrows and the presence of ocular ridges on the fixed cheeks, and is a convenient subgeneric group. Solenopleura a])pears to be of the sajiie character as many of the species placed under the genus Batiiyurus by Mr. Billings, and 1 think can be used for such forms as Bathyurus gregarius, Billings (Pal. Fobs., vol. i, p. 363), and nearly all the species referred to the genus Bathyurus from the Cambrian. The figure of the type species of So- lenopleura is copied on plate vi, ftg. 3. Among the species from the Saint John formation Ptycoparia Rabbi approaches most nearly to the typical forms of the genus Ptychoparia. Ptychoparia Robbi, Har Plate vi, figs. 1,1a. Conocephalites Eobbi, Hartt, 1868, Acadian Geology, Dawson, 2ded., p. .. ' Conocepluilitcg formoBun, Hartt, 18()8, Aciulian Geology, Dawson, 2dcd., p. Oo4. Description. — " Head without movable cheeks, of moderate size, de- pressed convex, slightly arched in front, where the width is consider- ably less than behind; length about equal to breadtii in fron.t. " Glabella ovate conical, sides straight, and doiyai iurruws so inclined as to meet if produced iu middle part of anterior ma'ff'j ; very convex; more elevated in the middle ; posterior furrows reachisig about one-third of the way across the glabella, directed strongly backwards, and reach- ing nearly to the base of the glabella ; middle furrows less distinctly marked, short, not so oblique as first ; anterior very short, appearing only as little pits or depressions on the sides of the glabella. ♦' Occipital ring narrow, convex, widest in the middle, narrowing to- wards the sides, which are turned forward, giving to it a crescent shape. Occipital furrow deep and wMI develoi)ed, widest in the middle, where it slightly impresses the base of the glabella ; narrow and slightly bent forward at the ends. Tiie ring bears a little, short, conical, tuber- cle-like spine in the middle, directed slightly backwards. (316) WALCOTT, I FAUNA OF THE SAINT JOHN FORMATION. 37 "Fixod clieckH, frontal limboni'tliird to oue-fourth of whole length of head, with » narrow, high, convex border, inside of which is a modor- at«'I.v deep furrow ; cheek-lobes (lepressed, convex, meeting in front, risiiij,' abrnplly from the deep dorsal furrow, on the borders of which they reach their greatest elevation, which, however, is not equal to that of glabella, and sloping thence roundly towards the sides and IVoiit. 'flie posterior limb bears a deep, wide, airrow, which widens somewliat near extremity. The marginal fold is very narrow and of httle prominence, and widens a little in the outer half. The posterior margin bendssilightly backwards at extremity of limb, which is rounded." On <'om|)aring the typo spetsimeus of P. Itohhi and P. formoaus^ and also a number of specimens of P. Robbi, I am unable to obtain gooil specific diflerences between them. The range of variation is slight and the two extremes are intimately united by specimens possessing the ciiaracters of each in a more or less fully developed condition. P.for- ntoum appears to have been founded on compressed specimens of P. liohhL The representative type of P. liobbi occurs in the Menevian of Wales as the very closely related species Pttjehoparia (=Conocoryphe) appla- luita, Salter (Quart. Jour. Geol. Soc, vol. xxv, p. 53, pi. xxv, figs. 1, L*, 4, 5). In Ptychoparia { = Solenopleura) cristata, Linuarssou (Afdrag ur Geol. Foreniugens, i Stockholm Fiirhandl. 1877, N:o. 40, Band, iii, N:o. 12, p. 370), from the Paradoxides beds of Sweden, we find an allied si)eciea, hiuI Mr. Linuarssou compares it with P. Emmrichi, the nearest represem.itive of the type in Bohemia. Formation and locality.— Camhrian. Saint .John formation, BatclifiTs Millstream, N. B. Ptychoparia OtiANGONDiANA, Hartt. Plate V, figs. 4, 4a-/. Conovephalites ouangondianus, Hartt, 1HG8, Acadian Geology, Dawson, 2cl ed., p. 651. Description. — " Head without movable cheeks ; strongly convex in outline, somewhat subangular in front ; much narrower iu front than ht'hind, where width is greater than the length ; width in front nearly oqual to length ; anterior margin wide, with a strong fold, whose axis is strongly inclined forwards, so that it presents a short, steep, convex sUipe forward, and a long, concave slope in the inner side, being much U'ss elevated than g'lbella or fixed cheeks. Glabella long, ovate-con- ical, nearly twice as wide posteriorly as in front ; very convex, slightly subanguhir at the middle ; sides straight, inclined to one another so as to meet in the nuddle of front margin if produced ; rounded in front ; casts sometimes showing three pairs of short, raised, transverse lines ou the sides of the glabella, occupying the position of the ordinary glabellar furrows ; of these the two posterior are directed obliquely backwards. In some specimens there seems to be a fourth pair in ad- (317) 111 , t A k4 CAMBRIAN FAUNA OF NORTH AMERICA. [bull. 10. WALCOTT. I III «■■'■ vauce of the other, represented by little tubercle-like processes situated on the side of the glabella in front, just where the sides curve to the front. Glabella very much more convex than fixed cheek. Occipital ring strongly arc)!ed upward, and separated from glabella by a well- marked groovb ; middle of posterior margin produced backwards in a short conical spine. Fixed cheeks highest along dorsal furrow, towards which they pressed abrupt round slopes, while their general surface slopes gently and quite evenly towards front of sutures. The dorsal furrows are confluent in front with the flat margin, so that the cheek- lobes do not meet in front. They are highest along the straight dorsal furrows, but where they bend to go round the anterior extremity of glabella, the cheek-lobes narrowing and curving towards each other, gradually sink away and disappear in the front flattened space. The ocular lobes are veiy well developed, forming subsemicircular lappet- like lobes, curved strongly upwards, and situated about opposite the center of the head. An ocular ridge, low and rounded, but very prom- inent, runs from anterior margin of ocular lobes, with a curve almost parallel with front margin of shield, but slightly divergent from it to the dorsal furrow, which it gains at a point considerably back of front of glabella, and where the straight part of the dorsal furrow bends to go round the front. Posterior limb short and broadly rounded. Post- marginal furrows less deep than dorsal ; wider ; margimd fold narrow and moderately p'^ominent ; shield strongly arched transversely ; sur- face smooth." This species is more fully represented by the centnil portion of the head than any other in the collection. The range of variation appears to have been small originally, but the distortion by lateral and ver- tical compression gives it a variety of forms. Three of these are illus- trated. A small head that appears to be uncompressed looks very much like that of P. {Solenopleura) cristata, Linnarsson. (See dc-acription of F. Rohbi.) Mr. Hartt speaks of this species as rather uncommon at Rat- clitt's Mill stream, but on examii>ing al? the duplicate material we tind upwards of forty specimens. From the character of many of the spec- imens it appears quite probable tljat some of this material was not be fore him when he wrote the notes on the species. Formation and locality. — OcUibrian. ►.'^aint John formation, Eatclitt's Millstream, N. B. PTYCHOPARIA OirANGONDTANA, var. AURORA, Hartt. Plato V, fig. 5. ConocejiluiUtes aurora, Hartt, 1668, Acadian Geologj', Dawson, 2d od., p. 653. Description. — "Resembles C. ovangondiamim, but differs in wider head, more depressed ; anterior margin more broadly rounded, and border more strongly reflexed and elevated." (318) To m< diana U give th( 8ubqua( importa variatioi and unit Fornm stream. Conocephali Descrij. slightly c fold, con A goes roun There a collection .it once ft rora, fron: rim and tl but two ti Formati a little noi Conocephalitei Conflcephalite Uescripti is of mediu thirds widt wide, low I arated froir ovate, coni< than in froi clined to on of margin ii Tbe glabell There are tl glabella, an they are api furrow narri die, narrowc WALCOTT. I FAUNA OF THE SAINT JOHN FORMATION. 39 To me the distinctive (jharacter between this species and P. ouangon- (liana is in the form of the glabella. Compression and distortion may give the depressed broader form and reflexed rim, but not entirely the subquadrate glabella, that appears to be a feature of original varietal importance. With a large series of specimens of this form showing its variations, the tendency will be to deprive it even of a varietal name and unite it directly with P. Ouangondiana. Formation and locality. — With the preceding species at Katcliflfs Mill- stream, N. B. Ptychoparia qitadrata, Hartt. Plate V, lig. 1. ConocephalUea quadrata, Hartt, 1868, Acauian Geology, Dawson, 2d ed., p. 654. Description. — "Head minute, transversely oblong, twice as long, slightly curved in front, straight behind, very flat ; a narrow elevated fold, convex in front, concave behind, and somewhat inclined backward, goes round the margin." There appears to be but one specimen representing this species in the collection. The strongly-marked subquadrate glabella distinguishes it at once from the associated species except P. ouangondianus, var. au- rora, from which it is Si^arcely separated by the character of the frontal rim and the stronger ocular ridges. The entire length of the head is but two millimeters. Formation and locality. — Cambrian. Saint John formation. Portland, a little northward of Saint John, N. B. Ptychopaeia Orestes, Hartt. Plate V, fig. 3, 3a. Conoceplialitea orestes, Hartt, 1868, Acadian Geology, D.a^son, 2d eil., p. 649, Conocephalitea Halli, Hartt, 1868, Acadian Geology, Dawson, 2d ed.,p. 654. Description, — " The head-shield of this species without movable chee'ko is of medium size, length about equal to breadth in front, or to two- tbirds width behind j margin arched moderately in front, with a rather wide, low border fold, widest in front, narrowing toward the sides, sep- arated from the rest of t!ie head by a shallow groove. Glabella long, ovate, conical, or cyliudrico-conical, extremely convex, wider behind than in front, where it ii^ rounded. The sides are straight, and so in- clined to one another as to meet, if produced, at a distance in advance of margin in front ab' .it eq*' . o the distance of that liiie from glabella. The glabella is flattened on the sides and never regularly convex. There are three pairs of furrows, which lightly impress the sides of the glabella, and of which traces are not always distinctly preserved, and they are apt to be otcn best in slightly distorted specimens. Dorsal furrow narrow, deep, and sharply cut ; occipital ring widest in the mid- dle, narrowed from behind at the sides, separated from glabella by a (3») ■'.f.- iM ■ (it &;J> -1 40 CAMBRIAN FAUNA OF NORTH AMERICA. [bull. 10. WALCOTT.] distinct furrow. Bears in the middle a minute tubercular spiue point- ing upwards Fixed cheeks strongly convex, but much less so than the glabella, meeting in front with abrupt slopes triiptly alo curve, whose considerably KliilH'')n abo 'i^lge i;, u.sua WALCOTT.) FAUNA OF THE SAINT JOHN FORMATION m ten are very close, and I had placed it with C. HalU under P. Orestes iu a preliminary study of the species. The material is so fragmentary and poorly preserved that it is dif&cult to satisfactorily determine the limits of many of the species. Formation and loeality. — Cambrian. Saint John formation, Eatcliff's Millstream, N. B. Ptychoparia tener, Hartt. Plate V, figs. 6, Ga, b. ConocephalUes tener, Hartt, 1868, Acadian Geology, Dawson, 2d ed., p. 652. Conocejihalitea neglectus, Hartt, 1868, Acadian Geology, Dawson, 2d ed., p. 654. Description. — " Minute, j^labella ovate-conical, truncate at base, rounded ill front, where it is about half as wide as at occipital furrow, slightly contracted behind, length about equal to width at occipital furrow, strongly de])r'\ispd convex, more elevated at base than at front, and higher ala- • ^Im "sed cheeks ; aspect varies with state of preservation of specii»^!7 > \: : . i,e, rounded, convex, or concave; the middle seemH to be incliuv j t< project back slightly over the occipital furrow, slopes abruptly to occipital furrow, which is moderately deep, wide, and nar- rowed, and slightly inclined forward at the ends, where it terminates abruptly ; bounding groove deeper than other grooves in head ; occipital ring projecting backward bodily beyond higher margin, with the axis of its fold Inclined more or less backwai'd, and produced in the middle into a short conical backward inclined spine ; anterior limb regularly arched, as if the outlines of the complete head were semicircular. "Fixed cheeks, anterior border broad, fiat concave, rising more or less abruptly to a sharp, thin, marginal fold; width between anterior ex- tremities of cheek sutures "qua! to or about twice width of glabella at base. Cheek-lobes but si ' - ii !y convex, and much more depressed than the i;labella. Ocular ri<:'.>8 rry distinct, thin, sharj), elevated ridges, that begin about inn'ci ci .» cr' oheek-lobes, just behind rounded front of glabella, runoutwan a , 'jacizward at an angle of 60° to 65° to the anteroposterior diameter. ^ o' me at first straight, but soon begin to bend backward more and more abruptly, forming st fragment of a s])ii'al, their extremities being slightly directed inwards. The width between the ocular lobes is about equal to twice the ler.gth of the glabella. The ocular ridges are inclined outwards and forwards. Another ridge of the same appearance begins a very sh«/rt distance behind the origin of the former, and on the very margin of the cheek-lobes, and, diverging from the margin nej-; ' opposite to the base of the glabella, bends off abruptly along the ,)' r< \"')r margin of the cheek-lobe, describing a curve, whose convexity lircctod backwards. This ridge terminates considerably outside of the ocular lobe, ..t a point distant from the ^labe'la about equal to half the width of the latter at its base. This xidge '\:^ usually found incliued in the opposite direction to the former, (321) '. t. E<,<1 < 1i: Ik l N' "^1 if ■•; f K -II TT" \k 42 CAMBRIAN PADNA OP NORTH AMERICA. fnt'ti.. 10. viz, inward and backward. Posterior margin of fixed cheeks moder- ately and regnlarly S curved, the inner halves carving forwards, the outer halves backwards, with a marginal fold most elevated in the middle, but much less so than the ridges of the cheek-lobe or the anterior fold. This fold becomes double at about the middle, by thie appearance of a groove running along its summit, and it appears to run out before reach- ing the lateral suture. The width between the posterior extremities of cheek sutures is considerably greater than between the anterior ex- tremities or between the ocular lobes. Glabella without furrows." This is a very striking and peculiar species, owing to the develop- ment of the sharp ocular ridges and the ridges between them and the glabella. Associated with P. tener is a form described by Mr. Hartt as 0. neg- lectus : Description. — " Glabella regular! s^^mi-elliptical ; length, exclusive of occipital ring, about two-thirds of ti ■. ^atbase, moderately convex. Highest at middle of base and sloping . a regular curve toward the front. Traces of two pairs of glabellar lurrows on the sides. Occipital furrow deep and concave. Occipital ring with straight parallel mar- gins, narrow, with a short conical spine directed upward." The type specimen, No. 341, of Mr. Hartt's list, shows Tae same ocular ridges as in P. tener and also the same ridges on the inner side of the palpebral lobes. The specimen has been compressed so as to shorten and widen the glal>ella, and give it the characters mentioned by Mr. Hnrtt. On the evidence of the material in the collection, it does not ai)pear to represent a distinct species from P. tener. Formation and locality. — Cambrian. Saint John formation, Portland, a little northward of Saint John, N. B. (322) FAUNA OF THE BRAINTREB ARGIIililTES. Wishing to examine typical si)eciinen8 of Paradoxides Harlani, the writer visited Boston, and through tl»e kindness of Mr. Alpheus Hyatt, curator in charge of the collections of the Boston Society of Natural History, he not only obtained Jiccess to the collection from the Brain- troe argillites, but the loan of such specimens as were wished for study and illustration. Mr. Alexander Agassiz also gave permission to use material in the collections of the Museum of Comparative Zoology, and Mr. N. S. Shaler pV'.ced his private collection at the writer's disposal. It is owing to these favorable conditions that I am able to present at tills time illustrations .and descriptions of the fauna of the Braintree ar- gillites. The first notice of the presence of fossils in the patches of argillite associated with the Quincy granite in the north end of the town of Brain- tree, IMass., was by the late Mr. William B. Eogers, who called the at- tention of the members of the Boston Society of Natural History to it when exhibiting specimens of a large trilobite i'onnd at Hayward's quarry (Proc. Boston Soc. Nat. Hist., vol. vi, p. 27, 185G). Subse- I quently Mr. JRogers traced the history of the trilobite described by Mr. Jacob Green as Pnradoxides Harlani, in 1834, and showed quite conclu- sively that it came from Hayward's quarry and was identical with the species found there. Mr. Henry D. Kogers published the best figure of the species yet given, with remarks on its discovery, «&c. (Geol. Surv. [Penii., vol. ii, p. 816, 1858). Numerous collectors obtained specimens of Paradoxides Harlani, but I it is not until 1801 that we find any notice of other species. Mr. Albert Ordway then states that lie had found a fragment of a trilobite similar to that described in the Paradoxides beds of Newfoundland, in associa- tion with Paradoxides Bcnnetti, and which he referred to the genus El- llipsocephalus. He also mentions the discovery of " a distinct fucoidal [impression which shows three branches, each about 4 inches long, but not sufficiently well marked to aflbrd any evidence with regard to its nature" (Proc. Boston Soc. Nat. Hist., vol. viii, p. 6, 1862). The small jtrilobito is probably the same as that subsequently described by Mr. R. |P. Whitfield as Arionellus = Agraulos quadrangularis (Bull. Amer. Mus. li^^at. Hist., vol. i, p. 147, 1884). Mr. Ordway also published a figure of Itlie head of Paradoxides Harlani, when comparing that species with iPamdo.vides spinosus, Boeck, which Mr. Barrande considered as identical pith P. Harlani (Bull. Geol. Soc. France, vol. xvii, pp. 545-548, 1860). In the year 1803 a restored figure of Paradoxides Harlani, by Mr. F. (323) - 43 • I 'A it;' s^ t«': ftfi i fflf 44 CAM BUT AN FAUNA OP NORTH AMERICA. [BULL. 10. II.''.,- ^.i h^"( .-■ \i\- 1 1' J I' I'-* m s.. '^ til 1 B. Meek, was published iu Diiiia's IMimual of Geology and repeated in each subsequent edition of the Mauual. This very well represents the general characters of the species. The publication of the second described species by Mr. Whitfield gives a stronger interest to the fauna, which is now increased by the addition of another species of trilobite, Ptychoparia Eogersi, and a si)e- cies of Pteropod, Jlyolithes Shaleri. In seeking for a fauna in the Cambrian system of North America to compare with that of the Braintree argillites, we are at once directed to the Paradoxides beds of Newfoundland by the almost perfect identity of the leatling type of each locality, Paradoxides Harlani and P. Bennetti. 1 think it has yet to be decided that the two are distinct species. By- oHthes excellens, Billings y"al. Foss., vol. ii, pt. 1, p. 70, 1874), is very closely related to JT. Shaleri, more so than to any other American spe- cies, and Agraulos sociaMs, Billings {loc. cit, p. 71), is of the same type as A. quadrangularis, Whitfield, as shown by figure 1 of plate vii. Ptychoparia Rogersi does not appear to be represented in the Newfound- laud Paradoxides beds, unless it be by Ptychoparia (Solenopleura) com- munis, Billings {loc. cit., p. 72). Mr. Barrande has shown the strong resemblance between Paradoxides spinosus, of the Bohemian Basin, and P. Harlani; and the Paradoxides beds of Sweden, Bohemia, Wales, Newfoundland, and Braintree have frequently been correlated in a general manner by authors. Genus HYOLITHES, Eichwald. Hyolithes Shaleri, n. sp. Plate vii, ligs. 4 4a-c. i'orm an elongate triangular pyramid, slightly arching towards the dorsal side and expanding regularly from the apex towards the aper- ture. Transverse section midway of the length, semielliptical, with a width twice as great as the height ; the lateral angles acute. Ventral face gently convex transversely, curving slightly longitudinally. Dor- sal face strongly convex, and showing a slight tendency to become angular at the center, a little concave longitudinally. From the direc tion of the surface lines the aperture sippears to have been oblique. Opercolum unknown. Surface marked by lines of growth thsit on the| dorsal side are nearly transverse, and on the ventral side arched for ward ; traces of fine longitudinal lines are shown in the matrix of the | ventral side. JHmciisions. — Tjength, about 90""" ; breadth of aperture, 23""° ; height I of aperture, about 14""". The apex is broken away, and the aperture a | little crushed by compression. The most nearly related American species is Hyolithes excellens, Bill I ings (Pal. Foss., vol. ii, pt. 1, p. 70, fig. 39, 1874), from Smith's Sound,] (324) WALCOTT.J FAUNA OP THE BRAINTBEE ARGILLITES. 45 Trinity Bay, New Foundland. Mr. Billings's description and figures lead me to think that the two species are closely allied, but still distinct, species. The specific name is given in honor of the discoverer of the specimen illustrated, Mr. N. S. Shaler, Paleontologist of Harvard University. Formation and locality. — Lower Cambrian. Braintree argillites, Hay- w!»:d'8 Quarry, South Braintree, Mass. Genus PARADOXIDES, Brongniart. Pabadoxides Harlani, Green. Plate vii, fig. 3; plate viii, figs. 1, lo-e; plate ix, fig. 1. Paradoxidei Harlani, Green, 1834, Amer. Joum. Sci., vol. xxv, p. 336. Rogers, Win. B., 1856. . -oc. Boston Soc. Nat. Hist., vol. vi, pp. 27-29, pp. 40-44 ; ibid., Stodder, p. 369. Rogers, Wm. B., also in Amer. Jour. Sci., 2d ser., vol. xxii, p. 296. Rogers, H. D., 1858. Geol. Penn., vol. ii, p. 816. fig. 590. Ordway, 1861. Proc. Boston Soc. Nat. Hist., vol. viii, pp. 1-5; I'&id., Jackson, p. 58. Dana 1863. Manual of Geology, p. 189, fig. 245. This figure appears in each subsequent edition of the Manual. Compare Paradoxidea spinosua, Boeck. Mr. Green's original description is as follows : Description. — " The contour of the buckler in this species cannot be satisfactorily determined from our present specimen ; the anterior and posterior parts of it are well defined, but the cheeks on each side are either mutilated or obscured. The front is very much elevated above the surface of the cheeks. It rises a little before the anterior edge of the buckler, is rounded in front, and gradually tapers towards the mid- dle lobe of the abdomen, with which it forms a regular continuation. On its posterior surface there are three transverse furrows ; the upper one crosses it a little obliquely, and there is on each side above a con- siderable protuberance. The cheeks were, no doubt, in the form of spherical triangles, but whether the outer angles terminated in acute prolongations cannot, from our specimen, be determined. The organs of vision appear to be entirely wanting. There are two shallow depres- sions on each side of the cheeks, commencing near the protuberances on tlie front, and running towards the lateral edges of the buckler. The posterior border of the buckler, where it joins the lobes of the abdomen, is marked by a transverse groove, nearly continuous with the lower transverse furrow on the front ; this groove at its commencement ap- pears to bifurcate outwards. The abdomen and tail cannot be distin- guished from each other. There are seventeen distinct articulations in both. The middle lobe is very convex, and is separated from the lateral ones by a deep channel ; it gradually tapers to an obtuse tip. In our specimen there is a small part of the tail of another trilobite deposited in this place, which at first sight api)ears to be a dislocated fragment (325) ■i',4 m ■la ■m l^:r' I hi- m 46 CAMBRIAN FAUNA OF NORTH AMRRICA. IBUIX. 10. 1 1'- i ^ ■ of jiir animal. The lateral lobes are flattened ; the costal arches arc very distinct near their insertion, and for about half their length, but towards their free extremities tliey are a good deal obliterated. There appears to have been a delicate membranaceous prolongation for a con- siderable distance beyond the solid portion of each rib. This organiza- tion is very apparent on the costal arches of the tail. There is a deep groove running obliqnely over the upper surface of each rib. Length of the fossil about 9 inches ; breadth, about 4 inches." Mr. Green did not know the true locality of the specimen sent to hiin by Mr. Harlan, and it was not until twenty-two years after that Mr. W. B. Kogers announced the discovery of ai)eciraeu8 of the same species at South Braintree, near Boston, Mass., identifying the locality of the spec- imen used by Mr. Green in his original description. The description is unaccompanied by figures, but fortunately Mr. Green made numerous casts of the type, one of which is now before me. It is the narrow form of the species, measuring 22"'" in length by about 14°'" in width across the back of the head, and 12"'" across the wi«lest portion of the thorax. The palpebral lobes and movable cheeks are broken away, also the pos- terior segment of the thorax and the i)ygidium is displaced. Mr. Green describes the species as having 17 thoracic segments ; but in a very fiue specimen now in the collection of the Boston Society of ¥ tural History, 18 segments are shown between the head and pygidium ; and Mr. Henry D. Eogers gives a very perfect figure with 18 thoracic segments. Mr. Ordway, in making a comparison between that species and the Bohemian P. spinosus (Proc. Boston Soc. Nat. Hist., vol. viii, p. 3), gives an outline figure of the head of P. Harlani, which is evidently a restored figure made up from fragments. At the request of Mr. J . D. Dana, Mr. F. B. Meek drew a figure of P. Harlani for the Manual of Geology', from more or less fragmentary speci- mens in Mr. Dana's collection. This is one of the best, but not the best (see Rogers's figure), representations of the species yet published ; but in the presence of 19 segments in the thorax, and the short extension of the posterior pleurfe and other details, it varies from specimens before us. There is considerable variation in the species in the relative length and breadth of individufils. In a form similar to the type, the length is 21"™, and the greatest breadth of the thorax 10"". In two broad speci- mens the length is 25'"" and SS""' ; the breadth of the thorax 1C«'° and 20°°'., respectively. This variation is also shown in the pygidium, as may be seen by comparing figs, 16, c, d of plate viii. In the head the great- est variation is seen in the contour of the frontal margin and the grad- ual development of the frontal limb and rim. On the small specimens the frontal limb is very short and more or less rounded. With the in crease in size, the space between the glabella and the marginal rim in- creases in width, and the latter broadens and flattens out. Our informa- tion respecting the posterolateral spines of the head is limited. On the j narrow form, fig. 1, plate ix, they extend back to a point opposite the | (326) i: )• WALCOTT.l FAUNA OP THE BRAINTREE ABGILLITES. 47 fourteenth thoracic segment ; and the movable cheek, fig. 3, plate vii, Hhows a long, well-developed spine. There is a limited range of varia- tiou iu the extension ot the pleuree of the thoracic segments, but the material for study is too limited to say what value may be placed upon it. In reviewing all the variations, I do not think that more than one species is indicated. A narrow and broad variety might be designated if thought desirable. Of American species of the genus Paradoxides, P. Bennetti, Salter (Quart. Journ. Geol. Soc, vol. xv, p. 552, fig. 1, 1859), from Newfound- land, is the most nearly related. The figure accompanying Mr. Salter's description appears to have been taken from a distorted specimen, as the two specimens now before me, although imperfect, show aform very similar to that of P. Harlani. Mr. Ordway has described the differences between P. Harlani, Green, aud P. Hpinosus, Boeck (Proc. Boston Soc. Nat. Hist., vol. viii, pp. 1-5, 18G1), and from my own observations and . comparisons I cannot but agree with Mr. Ordway that the two species are represented. Mr. Bar- raiide considered P. spinosua and P. Harlani as one species (Bull. Geol. Soc, France, vol. xvii, pp. 545-547, 1860). Mr. Barraude had the cast of the imperfect specimen described by Mr. Green to compare with speci- meus of P. spinosua, and photographs of three specimens sent to him by Mr. W. B. Rogers. The two species are, however, very closely related. Formation and locality. — Lower Cambrian. Braintree argillites. Hay- ward's quarry. South Braintree, Mass. Genus PTYCHOPARIA, Corda. ' PTYCHOPARIA EOGERSI, n. sp. Plate vii, fig. 2. This species is known only by the central portions of the head, and two specimens showing portions of the thorax. Glabella cylindro-conical, rounding rather abruptly iu front, posterior pair of glabellar furrows very faintly shown in one specimen ; dorsal furrow strongly defined; occipital furrow rounded, well marked and ex- tending out across the flixed cheeks; occipital ring rather narrow, rising at the center and extending backwards in a short, strong spine ; fixed cheeks of medium width, moderately convex, and sloping forward to unite with the frontal limb ; ocular ridges shown only on one specimen ; starting a little back of the anterior end of the glabella, they extend obliquely backward to the small palpebral lobe; frontal limb rather narrow; it curves downward for a short distance in front of the glabella aud then up to the frontal rim. The facial sutures cut the anterior margin so as to leave a narrow frontal limb, and then extend obliquely outward and backward to the palpebral lobe;_ back of this they extend obliquely outward to the posterior margin of the head. (327) i I' ! - ■I !■(■■;■ m '■■'■ m \fY m^^:^ li. • I ■ I 48 CAMBRIAN FAUNA OF NORTH AMERICA. [BULU 10. Thorax formed of well marked, strongly trilobed, narrow segments; the axial lobe about one-third of the entire width anteriorly, and taper- ing rather rapidly backward; pleural grooves very narrow. Number of segments in the thorax unknown. The condition of the preservation of the surface renders its character uncertain. It is apparently roughened or grauulose. Owing to the lateral compression of the specimen illustrated, the form of the glabella is too elongate. In hopes of getting better specimens the further illustration of the species is deferred. The specific name is given in honor of Mr. W. B. Bogers, the distin- guished geologist, who took so strong an interest in the discovery of the Braintree paradoxides beds in 1856. Formation and locality. — Lower Cambrian. Braintree argillites. Hayward's quarry, South Braintree, Mass. Genus AGRAULOS, Corda. Agbaulos quadrangularis, Whitfield. Plate vii, fig. 1. Ball. Aiiier. Nat. Hiut., p. 147, plate xiv, Arionellus quadrangularia, Whitfield, lb84 fig. 8. Description. — " Known only by the glabella and fixed cheeks, which are of small size, and as united are subquadrangular in form and depressed convex. Glabella quadrangular a little narrower in front than at the occipital line, squarely truncate in front and destitute of any appearance of glabellar furrows. Dorsal furrows bounding the glabella, deeply marked. Fixed cheeks about half as wide as the gla- bella, moderately convex in the middle. Frontal limb about as wide as the fixed cheeks, convex on the surface and strongly arched on the front border; no marginal rim exists. Palpebral lobes, one of which is visible, minute, and but slightly raised above the general surface of the fixed cheek adjacent. Occipital ring narrow. General surface smooth. This species is so entirely distinct in its quadrangular gla belli that there is no possibility of confounding it with any other Amer- ican species of the genus." We have two specimens of this species showing the central portions of the head and fixed cheeks. The glabella is more elongate and less quadrangular than in the type specimen which appears to be longitudi nally compressed, and also without the occipital ring and the postero lateral portions of the fixed cheeks. Restoring these parts in outline on the figure given by Mr. Whitfield, leads to the conclusion that "ve have but one species represented by specimens, varying considerably owing to their condition of preservation. The largest head is from the collection of Mr. N. S. Shaler, and measures 18"'"' in length. A smaller] head in the collection of the Boston Society of Natural History is 9" in length, and shows a small spine on the center of the occipital ring. (328) W/M.rinr.l FAUNA OF THE nRzMNTREE ARGILLITES. 49 The first notice of this species is by Mr. Albert Ordway (Proc. Boston Soc. Nat. Hist., vol. viii, p. 6, 1861), v 'lere he refers it to the geiiut) Ellil)socephalus, but does not propose ,i jpecittc name. Mr. J. Marcou had ii specimen in his collection for many jears, but it does not appear to have been h )ticed until studied by Mr. Whitfield. Formation and locality. — Lower Cambrian. Braintree argillites, asso- ciated with Paradoxidcs Harlani at Hay ward's quarry, South Braintree, Mass. (329) «1 hi Bull. 10- isO" ilring. m i;.f". I •I. ■ )• ON A NEW GENUS AND SPEOIES OP PHYIil^OPODA FROM THE MIDDIiE CAMBRIAN. Genus PBOTOOABIS, n. gen. Garapace without evidence of a dorsal sutore, rounded on the dorsal line, and bent downward on the sides ; without any rostrum. Body many -jointed — 31 segments extending out from beneath the carapace; the last segment broader than the preceding, and terminating in two spines. Type Protocaris Marahi. In comparing Protocaris (P. Marahi) with Hymenocaris (if. vermi- catida) (Salter, 1852. Bep. Br^c. Assi c, pt. 2, Notices and Abstracts, p, 58; Mem. Geol. Surv. Gt. Brit., vol. iii, y. 293, plate ii, figs. 1-4; plate v., fig. 25, 1866) we find that in tlie simple, iL>ent or folded eyeless shield or carapace they are closely related, but in the structure of the body they di£fer materially. Hymenocaris has, in one instance, 9 strong seg- ments shown in its more elongate body, the terminal one ending in three pairs of spines ; usually 6 or 7 segments are seen, 8 or 9 are less fre- quent (Brit. Assoc. Bep. 1883, p. 219). Protocaris has 30 narrow seg- ments, a large terminal segment or telson with two rather strong caudal or terminal spines. i ,3 Pbotooabis Mabshi, n. sp. Plate X, fig. 1. i The specimen on (^hich the genus and species is founded is com- pressed between the laminsB of the slate so that the entire outline of I the carapace is shown and the body is widened out. As flattened the | carapace is rounded, quadrangular in outline, with a more or less dis tinctly defined marginal rim all around. The general surface appears | to have been smooth. No evidence of eyes. The body projecting beyond the carapace is about two-thirds as long | as the carapace, narrows posteriorly, and is made up of numerous nar- row segments, each about one-third of a millimeter in breadth ; the last I segment or telson, which is 2.5°"^ long, supports two caudal spines? or 8°"" in length; 30 segments appear between the posterior edge of J the carapace and the telson; the segments appear to have been I smooth and without a spinose or crenulated posterior margin ; the tel I son and caudal spines also appear to have been smooth and withontj ornamentation. (330) 60 WALCOTT.) NEW GENIJ8 ANU srECItS OF PHYLLOPODA, 51 IHmennionii. — Total It'iigtli, 42"""; length of carnimce, 21""" ; width, 20111111 . length of body, !/>"'"', t'xt!lu8iv« of ciiudal spines; width of body, where it passes beneath the carapace, 10"'"' ; at tolson, 4""°. The 8])eciflc name "s given in honor of Prof. O. C. Marsh. Formation and locality. — Middle Caiubri{in. Georgian formation. Parker's farm, town of Georgia, Vt. (331) If •^ ■p m **' W'- m ii Acadian Groi Acrothele ... Ma. AKassiz, Ales Agnostna ... Acai bren Cam iotef Inter -■VeoE fiimil Agreulos affinii cetice longi( qnadi social] strenn Anopolenns . . . Arionellns qnat =A Barrande, Mr. . . ilathyurus gteg. = So Billings, E Bohemian Basin Parad Boston Society o Braiutree argillit Cambrian faunas Cambrian, Middli of P systea Carboniferous syi Cold Brook = Poi Conception Bay, S Conocephalites... A B{ el< foi ge: Ha Mi ncj On On; Oai INDEX. [Fignrea in heavy-faced type Indicate the page on which the description is given.l Page. Acadian Oronp, Kote on , S Acrothele 15 Matthewi J1,I5, 16 Agassiz, Alexander 43 Agnustus 22 Acadiona 11,12,13,9a brevifrona 12,23 Cambrenaia 12 integer 13,23 iDteratrictna 23 Neon 23 Mimitia 22,23 Agraulos 4fl affinia 13,14 ceticephalna 14 longicaphalna 14 qnadracgnlaiia 14,44,48 aocialis 13,14,44 atrennns 13,14 13 48 43 44 36 13 Anopolennu Ariuoellua qnadrangnlaria = Agraoloa qnadrangnlaria. . . Barrande, Mr Batliyurus gregariua = Solenopleura gregarina Billings, E 13,25 Bohemian Basin 44 Paradoxldea fanna 13 Boxton Society of Katnr?! H' atory C3 Braiutree argillites U, 43 Cambriau faunas of North America 9 Cambrian, Middle, new genus and apeciea of Phyllopoda frori 49 ayattim. Note 11 Carboniferous system 9 Cold Brook = Portland 30 Conception Bay, Speciea from 13 CoDOcepbalites 12 Aurora..." 3? BaUeyi 29,32 elegana 33 formoina 36 gemini-apinoana 28,30 Halll .39,40,41 Matthewi 28,30 neglectua 41,42 Oreatea 39 Onangondiannm 40 Oaangondianna — 87,38 Page. Conocephalites quadrata 39 Eobbi 86 tener Thersites Aurora = Ftychoparia Ou- angondiana,var. Aurora formosus = Ptychojaria Eobbi gemini-spino8U!i=Conoco- ryphe Matthewi Halli = Ptychoparia Ores- tes r.cglectns = Ptychoparia tener Thersites = Ptychoparia Orestes, var. Theraitea. . Conocephaliis striatus 35 Sulzeri 35 Conocoryphe 28 bnfo 12,84 coronatus 13, 29, 30, 35 Dalmani 12,34 elegans 11, 13, 13, 33. 34 emarginata 34 ezsulans 12,29,35 Haguoi ... 35 Matthewi 11, 12, 13, 98, 30, 35 Solvensis 12,29,35 Sulzeri 13,85 tenuicincta 34 Walcotti 11,30 (Elyx.) iaticeps 30 (Salteria) Bailey i . . . il, 12, 13, 39, 33 (SaltPrla; venulosa 12, 33 (Subgenus?) ilatihewi 98 Crepicophalus lowunsis 35 = Ptychoparia Hagnei 36 Ctoiioccphalus 36 Dawson, J. "W., Note 9 Discina Acadica 10 Elliptocephalua 12 Eooyatitfli 14 primaevua 11, 14 Eodiscua pulchellaa 24 Eophyton 12 Erinnya venulosa 31 Faiiua, Bohemian Parudoxidea 12, 18 Braintree argiUitea 43 Cambriau of North America 9 (333) 54 INDEX. Fanna, Manuel's Brook Henevlan, of Wales Korth America, Cambrian. Swedish Paradoxides Page. 18 12 9 12 Saint John 9,12,13 Green, Jacob 43 Group, Menevian, of Wales 11 Saint John 9 subgeneric, indication of 12 Hartt,C.P 10,18 collection 9 Harttia 18 Matthewi 11,19 Hnronlan rock 9 Hyatt, Alpheus 43 Hyiiienocur*' 50 vermicauda 50 Hyolithes 12,20,44 Acadioa 11, 30 aclis 20 AmericanuB 20 cinctus 11,13,21 Danianus 11, 13, ao, 21 excellens 13, 14, 44 Micmac ll,at primordialis 11,20 Shaleri 14,44 Lingula 15 1 Dawsoni 11,15 15 15 36 U d,i:> 12,13 ferruginea Matthewi LiostracuB — Manuel's Brook, fauna of Matthew, G.F Mei-nvian group of Wales 11 Microdiscus Co Dawsoni 11,13 as, 24 pulcheUus 21,24,25 puuctatus 11 , 12, 13, a4, 25 spociosus 25 Middle Cambrian, new genus and species of Phyllopoda from 50 MuiTay, Alexander 13 Museum < ' "^omparativo Zoology 43 New genus . species of Phyllopoda 50 North America, Cambriuu fannns of 9 Obolella .^ 16 ? miser 13 sagittnlis 12,10 transversa 11, 12, 16 sp 11 sp. undt 16 OboluH (Discina) nitida 10 Olenellus asaphoidvs i;t Orthis 17 Billingsi 11,17,18 exporecta 18 Hicksi 17 sp 11,18 Ord way, Mr 43 Palffincmea 19 JAoadica 11,19 Palteophycns 12 Paradoxiues 25, 45 Page. Paradoxides Aoadicus ... 10, 11, 2;! Bennett! 13,14,43,44,47 decerns 13 Eteminicus 10, 11, ST Eteminicus, var. breviatus. . .10, 11, 27 Eteminicus, var. Mali'-.itus. . . 10 11, 27 Eteminicus, var. pontiflci'Ws .10, li, 27 Eteminicus, var. Quacoonais. 10, 11 Eteminicus, var. suricoides . .10, 11, 27 fauna 12 fauna, Bohemian 13 fauna, Menevian 12 fauna, Swedish 12 Hariani 14, 43, 44, 45, 46, 47 Hicksi 14 lamellatus 10,11,35 lamellatns, var. Loricatns — 10, 25 Micmac 10 rugulosus 13,27 slates of Saint Mary's Bay, Newfoundland 13 sp 13 spinosus 43, 44, 45, 40, 47 tenellus • 13 ( Anopolenus) vennstns 13 Phyllopoda, new genus and species of 50 Protocaris, n. gen 50 Marshi, n. sp 30 Protocystites Menevensis 11, 15 Ptychoparia 12,34,47 applanata 12 cristata 12 Emmrlchi 13,14,35,37 formosus 37 Haguei 35,36 Linnarssoni .''0 Orestes 11,13,39,40,41 Orestes, var. Tliersites 11, 40 Onangondiana 11,37, ;iO,40 Ouangondiana, var. Aurora. . 11, 3§ Onangondianus, var. Au^-ora. 39 quadrata 11, 39 Robbi 11,12,1.3,36,37,40 Rogersi 14, 44, 47 striata 35,36 tener 11,13,41,42 = Conocephaln8 34 (=Conocoryphe) applanata . 3" (Crepicephalus) lowensis 36 (Solenopleura) communis 13,44 (— Solenopleura) cristata 37, 38 Rogers, William B 43 Saint David's section of Wales U Saint Jolm faunn, 12,13,14 formation. Application of the name of 9 group. Note as to the use of the tenn of 9 group. Plant remains of the higher divisionsof 12 Saint Mary's Bay, Paradoxides slates of. . 13 Salterella 13 Salteria 12,31 BaUeyl 32 (334) INDEX. 55 Salteria venulosa Scenella reticulata Shaler, N. 8 Solenopleara Stenotheoa •• pauper Straparolina remots Swedish Faradozidea fauna. . . System, Cambrian, Note as to Fage. 12,32 13 43 38 19 13 13 12 System, CarboniferouB .... Triaasic Iheca Aoadica Triassic system Wales, Menevian fauna of. Williams, H.S Whlteave8,J.P Whitfield, B.P PftJta 9 9 20 9 12 10 13 10,43 11 (335) 11^ 1 ■,■■■ Plate I. Page. Fig. 1. Orthis Billingsi 17 1. Cast of a ventral ? valvo bavingfascicnlato or bifurcate costa;, en- larged to two diameters. la. A small ventral valvo doubtfully referred to this species, en- larged to three diameters. 16. Cast of a ventral valve with sliarp radiating costai, enlarged to two diameters. lo. Exterior surface of a dorsal f valve marked by simple costa) crossed by fine concentric undulating strito, enlarged to three di- ameters. Id. Interior cast of ventral ? valve, enlarged to two diameters. Pig. 2. EOCYSTITES I'RIJIiEVUS 14 2. Enlargement to four diameters of a single plate. Fig. 3. Hahtia Matthewi 19 3. Interior of shell, enlarged to twelve diameters. Fig. 4. ACROTHELE Mattiiewi 15 4. Dorsal valve, enlarged to two diameters. 4a. Supposed ventral valve, enlarged to four diameters. ' Fig. r>. Obolella transversa 16 .'). Interior of ventral valve, enlarged to eight diameters. 5a. Cast of the interior of the dorsal valve, enlarged to six diameters. Fig. 0. Pal^acmea 1 AcADiCA 19 6. View of the typo specimen of Dischia ^Icadica, Hartt, enlarged to two diameters. (336) "« :# H. (;EOI.0i;iCAr. (illiVKV mi.i.KiiN so. 10 I'l.. I \^; 4ri 'm -I'H itii.vcmopoMA AM> (iA>ri:uf)roi)A. |f'i*l lli^l !• if >i|> J-!J'-V i Plate II. Fig. 1. MIORODI8CU8 PUNCTATU8 24 1. la, b. Head shields showing variations, enlarged to four diameters, lo. Pygidium, enlarged to three diameters. P'ig. 2. Agnostus AcADicus 22 2a. Head shield, enlarged to three diameters. 2. 2b, 0. PygidiiB, enlarged to three diameters. Fig 3. M1CRODI8CU8 Dawsoni S3 3. Head shield, enlarged to three diameters. 3a. Pygidium, enlarged to three diameters. Fig. 4. HY0LITHE8 4. Interior cast of operculum, enlarged to four diameters. 4a. Exterior of operculum, enlarged to four diameters. Fig. 5. Hyolithes AcADiCA 20 5. Ventral face, natural size. Fig. 6. Hyolithes MicMAC 21 6. Enlargement to two diameters of the typt ecimen. Fig. 7. Hyolithes Danianus 20 7. Dorsal view of a portion of the shell, enlarged to two diameters. 7a. Ventral side, enlarged to two diameters. 7b. Side view to show the curvature of the shell, enlarged to two diameters. (338) 68 Kfl V. 8. (lFOI,0(ilCAL BUIIVF.Y ^ImI mm ■ r -i' S; PffiCILOPODA AND PTEUOPODA. Jj 4" rww i'-' Plate III. Fig. 1. Paradoxides Etkminicus 1. Variety snricoides (after Matthew). la. A Hiiiall ])ygi(1iiiin (after Matthew). 1ft. Medium Hizert head, Ihittoiied (after Matthew). Ic. Variety hreriatiiH (after Matthew). hi. Variety poniijicalh (after Matthew). If, Head of a young iudividnal in the Hartt collection shortened by eouipreNsioii, enlarged to four diameters. 1/. Head of a young iudividnal showing wide frontal rim, enlarged to two dianietf'rs (after Matthew). 1(/. Head sliowing narrower frontal rim than fig. 1/, enlarged to two diameters (after Matthew). Pagti 2r Fig. 2. Pauadoxidks lammellatus 2, 2a. The two type specimens of the species, diameters. 25 2a is enlarged to two Fig. 3. Pahadoxides Acadicus , 15. A distorted specimen showing the pygidium and porMous of the thorax and head, enlarged to two diameters. 3a. Head; natural size. 25 60 (340) IV ■i 1 in|in£ |; mW' ' ip m%f ., m ^ I 25 25 IHKflLOl'ODA. t *.'* m ' '*■'. I ' i U. !s. <:i:oLO I. I • f' ■-■.'. [ii,l/v-.; Plate IV. Fig. 1. CONOCORTPHB MATTHEWI 1. Head compressed longitudinally. la. Head compressed a little laterally, bnt nearly in its normal form. lb. Finely granulose variety, enlarged to two diameters. Fig. 2. CONOCORYPHE ELE0AN8 2. 2&. Heads, natural size. 2a. Side of head, witli genal spine attached, enlarged to two diame- ters. This may belong to C. Matthewi. Fig. 3. CoNocORYPHE (Salteria) Baileyi 3. Large head, enlarged to two diameters. 3a. 8ide of head, with genal spine attached. See plate v, figs 7, 7a. (342) Page. 33 33 III! IfHQlHj L-. S. CKOLOfilCAl. 81JUVRV IIULLETIN NO. 10 I'L. IV m i'(i;c'ii,()P(U)A. i» ■'■m ,1 , i ■ ,. 1 ^u: K u « fmm .-.■'' * , , m fill.:., fr- ! I Plate V. Paga Fig. 1. Ptychopakia quadrata 39 1. Typo specimen, enlarged to two diameters. Fig. a. Ptychoparia OuESTES var. Thkrsites 40 2. Typo o{ Conocephalites Theraitea, llartt, eularg&d to two diameters. Fig. 3. Ptyci-'OI'ARIA Orkstes 39 3. Typo of Conocephalites Halli, Hartt. 3a. Type of C. Orestes. Fig. 4. Ptyciioparia Ouangondiana 37 4. A specimen with the frontal furrow nearly ohsolete, enlarged to three diameters. 4fl. Free cheek associated with the head of this species. 4b. Distorted specimen referred to this species as a varietyby Mr. Hartt. 4c, A young head preserving its natural convexity and outline, en- larged to three diameters. 4d, 4/. Two examples showing variation in form, enlarged to two diameters. 4e. Type of the species a little distorted by lateral compression, en- larged to two diameters. . Fig. 5. Pt YCHOVARiA Ouangondiana var. Aurora 38 5. Type of Conocejihalitea Aurora, Hartt, enlarged to twj diameters. Fig. 6. Ptyciioparia tener 41 6. C6. Types of the species, enlarged to two diameters. 6a. Type of Conocephalites neglecttis, Hartt, enlarged to two diame- ters. Fig. 7. CoNocoRYPHE (Saltj:ria) Baileyi 32 7. Pygidium. 7a. Portion of the thorax, enlarged to two diameters. See plato iv, ligs. 3, 3a. Fig. 8. LlNGULA f Davsoni 15 8. Ventral valve, enlarged to four diameters. en ,2 'W;« m 1 ■' '• I 1.- f. •■-. (iKoi.omrAr, sukvkv J^ An 4h M Pn 4e PdCCII.Ol'Ol) i. HirLLRTIN SO. 10 M.. V Hrt a (J?) mi llj' Ml |t^!. w y ■t w: '■■1'-l . ' '1 \ ■ ,' * ■ ^4 ■■■ k ■*■''' i. ■ ■ 1 . , ■■■f, i" Plate VI. Psgft Fig. 1. Ptychoparia Robbi 3& 1. Type of the species, enlarged to two diameters. la. Typo of Conocephalitea formofius Hartt, enlarged to two diame- ters. Fig. 2. Ptychoparia (Crkpicephalus) Iowensis 1 36 2. Head exclusive of the free cheeks. 2a. Pygidiuiu. Fig. 3. SOLENOPLEUKA HOLEMATOPA 36 ."l. Type of the gouiis (after Angelin). Fig. 4. Ptychoparia striatus 4. Typo of tlie genus. Figure taken from Barrande. Fig 5. LIO8TRACU8 ACULKATU8 5. Type of the genus (after Angelin). Fig. 6. Ptychoparia Haguei 36 6. Typical form of the genus Crephicephalus of Hall and Whitfield. Fig. 7. Ptychoparia Emmrichi 7. Second type of the genus Ptychoparia, Corda. Figure copied from Barrande. (346) 66 1 C. -,. (iKOLOOICAI. MUltVKV Ut'LLKIIN NO. 10 n„ VI la pcEClLoi'on.v. I:- i', ,.^- ''I '■ii I'' . \ inl.' mi m iMi \\ vM Plate VII. Page. Fig. 1. AORAULOS QUADRANGTJLARIS 48 1. Head exclusive of the free cheeks. Natural size. Collection of Prof. N. S. Shaler. Fig. 2. PXYCHOl'AniA EOGERSI 47 2. View of type hpecimen. Natural size. Collection of Prof. N. S. Shaler. Fig. 3. Paradoxidks Haklani 45 3. Large iice cheek flattened by comiression. Collection of Boston • Society Natural History. lig. 4. Hyolithes Shai^.ri 44 4. 4a, 4b. Dorsal, ventral, and lateral, vievt;. Natural size, 4o. Transverse section. Collection of Prof. N. S. Shaler. (343) 'ti n. a. oEOLOoiCAt, Bunvr.v I1ULI,KT!.N NO. 10 I'L, VII ''^ ft;)- l.-l- I'TKUOI'ODA AM> I'll (.II.i I1M)|>,V. m Ill- ''A '''•:i',' r.i' tH' ^^H i ] , ', 'li.-.. ^1 ; 1 t'v ti J; r I 1 i 1 1 i mJ wm I • '■ aV /■■III -:■ 'Hi ■■■'• ■ ■, I', ». liEOLOCin Plate VIIT. Fig. 1. Pabadoxides Harlani 1, la. Two raediam-sized lieada, showing variations in the frontal border. Natural size. Oolloction of Museum Comparative Zoology, Cambridge. 16, Ic, Broad and elongate form of the ))ygidium. Id. View of the four posterior thoracic segments' and pygidium ; the latter ia crowded up beneath the segments. Collection of Prof. N. S. Shaler. le. Large hypostoma attached to the frontal doublure of the head. Collection of Prof, N. S. Shaler. Page. 45 70 (350) r. a. i^KOLOfiinA;, slhvky lUM.Ull.S so. 10 I'! . VIII \(i Id i4 lU'^ i'i^tr»A. mm '# '^'M ^1 it 'f fi' '"■ ( Plate IX. Pig. 1. Pabadoxides Harlani 1, A large individual preserving the body and parts of the head. The light colored portions are restored and the pygidinm, which is pushed a little out of position, replaced. The speoi- nien is from the collection of the Boston Society of Natural History. (352) 72 P»g«. 45 I ,M i P»ge. 45 r.n 1! I'. H. (ii;ol.()(ll( Al. .HIIKVKV i' iM t :«5 'W) lir ^M l5a of convenient size. To facilitate this, each Bulletin will have two paginations, one proper to itself, and one which bolonga to it aa part of the volume. Of thia series of Bulletins Kos. 1, 2, 3, 4, 5, 6, 7, 8, S and 10 are already published : 1. On Hypersthene-Andesite and on Triclinic Pyroxene in Augitio Bocks, by Whitman Cross, witli > Geological Sketch of Buffalo Peaks, Colorado, by S. F.Emmons. 1883. 8°. 42 pp. 2 pi. Price 10 cents. 2. Gold and Silver Conversion Tables, giving the coining value of Troy ounces of fine metal, Sic., b; Albert Williams, Jr. 1883. 8°. ii, 8 pp. Price 5 cents. 3. On the Fossil Faunas of the Upper Devonian along the meridian of 70° SC, fh>m Tomplimi County, N. 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