,\ MONOGRAPH FRESHWATER UNIVALVE MOLLTJSCA UNITED STATES, INCLUDING NOTICES OF SPECIES IN OTHER PARTS OF NORTH AMERICA. BY S. S. HALDEMAN, Professor of Zoology in the Franklin Institute, and Vice-President of the Entomological Society of Pennsylvania; Member of the Academy of Natural Sciences of Philadelphia ; of the Boston Society of Natural History ; of the Association of American Geologists and Naturalists ; and of the Societe" Cuvierienne of Paris, etc. PHYSAD^E. PHILADELPHIA: E. G. DORSEY, PRINTER, LIBRARY STREET. 1842. MONOGRAPH FRESHWATER UNIVALVE MOLLUSCA UNITED STATES, INCLUDING NOTICES OF SPECIES IN OTHER PARTS OF NORTH AMERICA. BY S. S. HALDEMAN, Professor of Zoology in the Franklin Institute, and Vice-President of the Entomological Society of Pennsylvania; Member of the Academy of Natural Sciences of Philadelphia ; of the Boston Society of Natural History ; of the Association of American Geologists and Naturalists ; and of the Societe" Cuvierienne of Paris, etc. PHYSAD^E. PHILADELPHIA: E. G. DORSEY, PRINTER, LIBRARY STREET. 1842. BIOLOGY IBRARY G Tant que Ton n'a etudie et recueilli que les seules Coquilles, les Testaces terrestres et fluviatiles ont ete negliges, parce qu'ils offrent moins de varie- tes dans les formes et moins d'eclat dans les couleurs de leurs enveloppes pierreuses, que ceux qui habitent les eaux de la mer. Mais lorsque voulant prendre de ces etres singuliers une connaissance un peu plus approfondie et plus philosophique, on s'est mis a examiner les animaux eux-memes, les especes de terre et d'eau douce sont redevenues un objet principal d'atten- tion, parce qu'il est plus facile de se les procurer avec leur animal vivant. Cuv. re It will enlarge their views beyond the feverish expectancy of a precocious and questionable celebrity, so easily and unworthily attainable, by the esta- blishment of insulated remarkable genera; for it is only by taking up groups, and thoroughly discussing them, that the progress of the science can be at all promoted. W. E. Shuckard, Cab. Cyc. Insects, p. 162. The genus Limneus is at present ill understood; many of the species being ill defined, and no two authors, except mere copyists, agreeing which are veritable species and which varieties; in fine, it may be truly designated " rudis indigestaque moles." To disentangle the species, and rectify the errors of authors, would, I fear, in the present state of our knowledge, require greater talents and perseverance than fall to the lot of the generality of mankind. Neither the influence of external circumstances, nor the great differences observable in the various periods of grow : th, appear to have been hitherto sufficiently investigated; and a correct monograph of this genus would not only require the lyncean eye of a Jenyns, but the searching skill of a host of less accomplished auxiliaries. Kenyan, Mag. Nat. Hist., vol. vii. p. 379, anno 1834. TO THOSE WHO LABOR FOR THE ADVANCEMENT OF THE DIFFERENT BRANCHES OF NORTH AMERICAN ZOOLOGY, THIS CONTRIBUTION TO THE SCIENCE IN WHICH WE ARE ALL MUTUALLY INTERESTED, IS RESPECTFULLY INSCRIBED, BY THEIR FELLOW LABORER, THE AUTHOR. 369569 PREFACE. This series of monographs was undertaken, not only to give an account of the species, but also of the varieties, and, as far as the material at hand would permit, to indicate the extent of variation and its possible limit, if there is such a limit in nature. We do not, in fact, know a species properly until we are acquainted with the different appearances it assumes, and the approaches it makes to other species. Some species require years of study from ex- tensive series, with an examination of the entire animal, and observation of their habits in their native localities ; but under the most favorable circumstances doubtful points will remain, because many species are less distinct in nature than they are represented to be in books. In the plates, the longitudinal lines made 6 PREFACE. to the conchologists of the country for aiding him in various ways, among whom may be mentioned Mrs. Say, Messrs. Adams, Anthony, Binney, Blanding, Conrad, Couper, Emerson, Gould, Lea, LeConte, Lewis, Mighels, Nuttall, Phillips, Poulson, Wagner, Wood, and Whit- temore. PHYSAD.E. Gasteropodous monoicous inoperculate pneumobranchiate testaceous aquatic mollusca; having a single pair of triangular or filiform contractile tentacles, the surface of which is covered with vibrillse,* and having the eyes at their internal base: the shells are thin in tex- ture, of uniform tints, and with the margin of the aperture sharp. The family LIMNEANA of Lamarck, belongs to Cuvier's Pulmonifera aquatica, of his order Pulmonifera, and class Gasteropoda; to Blain- ville's family Limnacea, of his order Pulmono- branchiata, and sub-class Paracephalophora * CILIA of authors, which term, however, was preapplied, and is still used, for hairs or bristles of a certain character. Thus the mouth of an animalcule, and the legs of an acarus, are both said to be ciliated. My friend Professor Bailey, an acute microscopist, approves of the term I have proposed for these vibratile organs. D PHYSAD^E. monoica; and to Ferussac's order Pulmonalia inoperculata, and sub-order Hygrophilidse. They live in the water, but most of the genera are obliged to come to the surface occasionally as they breathe air. From the lightness of their shells, they possess in an eminent degree the power to move along in an inverted position, with the foot applied to the surface of the water, thus affording the observer an opportunity to examine the oral organs when put into opera- tion by the animal. The foot is adapted for a more rapid locomotion than most of the preced- ing families possess. This is particularly ob- vious in Physa, which is the most active, and, as I believe, the most highly organized genus in the family. The members of this family are generally confined to stagnant waters, or those parts of small streams which are not liable to be continually rippled, as this would render the opening of the branchial cavity at the surface a matter of some difficulty. The foot appears to be covered with a secre- tion which has a repulsion towards water, as that organ will form a concavity at the surface, into which the water will not readily flow; but when this cavity is so far withdrawn that it PHYSAD^E. 7 becomes filled, the animal generally descends.* I have occasionally observed some individuals to become detached from the bottom, and rise suddenly to the surface;t but this generally happens when they have crept down along some object, with a very full supply of air. Some of the species have the power to ascend and de- scend, by expanding and compressing the volume of air contained in the branchial cavity, a method more simple than the one which Doctor Buckland has demonstrated to exist in the Nautiloid family. I have thus observed Physa heterostropha slowly to rise through the water, open its foramen, and descend again with an equally slow motion.^ Without a power of this kind, these animals would not be able to attain the surface, in situations where they might accidentally be deprived of aquatic plants, or other extraneous bodies, to which they * On some occasions, however, it becomes necessary, in addition to the withdrawal of the foot, to allow a few bub- bles of air to escape, before a sufficient specific gravity is attained to allow the animal to sink. f Loudon's Mag. Nat. Hist., 1830, vol. iii. p. 532. $ It has the power also of ascending and descending in water a few inches deep, by the aid of a glutinous thread. 8 PHYSAD.E. might attach themselves. That the density of the internal and external air is sometimes dif- ferent in this family, and in the terrestrial Pneumobranchiata, is proved by the slight clicking sound that frequently accompanies the opening of the branchial foramen. The head varies somewhat in shape, but is never decidedly proboscidiform as in the more highly organized Melaniadse. I have never been able to discover that the Limneans or Helices possess true organs of vision; but it is probable that they can distinguish light from darkness. In the other freshwater families de- scribed in this work, the power of vision, or sensitiveness to the action of light, is rendered evident by intercepting it with an opaque ob- ject, when they instantly retract; and I have even observed the protruded branchial canal of Unio radiatus (Gmelin) to be suddenly with- drawn, when subjected to the same experiment. I have ventured to name this family from what I conceive to be the principal genus, after repeated examinations of them. It is, however, so difficult to determine the question of supe- riority of structure, in animals whose organiza- tion rests upon the same model, that the result PHYSADJE. 9 must, in general, be considered as assumed, rather than as demonstrated. As linear ten- tacles appear to constitute the normal form among the mollusca, their triangular form in Limnea, would seem to point out this genus as presenting the most important distinctive cha- racter; but on similar grounds we might place the Helicinse above this family, on account of the situation of their eyes, and the possession of an additional pair of tentacles; whereas, they are much less highly organized than the Lim- neans;* and we might place Ancylus at the beginning of the latter family, because it is the uniting link between the hydrobranchiata and pneumobranchiata. Malacologists are universally agreed, that with the genera Physa, Limnea, and Planorbis, * In a cancelled portion of my manuscript, written under the impression that Limnea should stand at the head of the family, I remarked that "I at one time considered the genus Physa to stand higher than Limnea, judging from their habits, and considering the mantle as indicating a more complex organization; but these views were counter- balanced by the belief that sinistral animals do not occupy a more elevated station than their congeners, because, from the rarity of reversed genera, they may be viewed some- what in the light of monstrosities." i 2 10 PHYSAD.E. this constitutes a natural family, the only dif- ference of opinion arising upon the order in which they should be placed. Mr. Swainson places Planorbis at the head, because the shell represents that of Nautilus; a consideration which would have prevented me from giving it this position; because an animal cannot represent a different one, however high, and be the typical representative of its own family* The principal difference of opinion, however, has been upon the question whether Ancylus does or does not belong to the family. In one work, it is con- sidered a Patella; in another, a Crepidula; whilst one party asserts that it breathes air, another, that water is its only respiratory me- dium. Amidst this contrariety of opinion, the principal modern authors have placed the genus in the family now under consideration, but more, I suspect, on account of the great similarity of the soft parts, than from any certainty as to * Mr. Swainson places Corvus at the head of the in- sessorial birds; and if the carnivorous genus nearest allied to it, is to be considered typical, Buteo will stand above Falco, among the falconine birds ! The genus Perca stands as the representative of its class, although there are many genera which are more nearly allied to the reptilia. PHYSAD.E. 1 1 what medium they breathe. This resemblance is so apparent, that it would be likely to induce one to believe the genus strictly pneumo- branchiate, without evidence of a contrary nature; and the impossibility of determining its position as a hydrobranchiate mollusc, must have had its influence in retaining it among the Limneans. For my own part, whilst I had no right to contradict the respectable authority in favor of free air being the medium of respiration, my own observations convinced me that our Ancyli, at least, breathe water. I found them attached to the lower side of stones, in rapid water, within dead bivalve shells, and in such situa- tions generally, which they could never have attained from the surface. Moreover, I never saw them at the surface of the water, even in vessels under my own eye. I now suspected that, occupying so debatable a ground, the branchiae of this genus might be adapted in- differently to aquatic or aerial respiration, and I was confirmed in this view, by the discovery of a hydrobranchiate Physa (see Physa globosa) in Tennessee.* * I would recommend to naturalists to travel in their 12 PHYSAD^E. It results from these facts, that Cuvier and Ferussac were wrong in naming this family Pulmonifera and Pulmonalia; and I believe we are indebted to Lamarck, for having been the first to indicate the respiratory organs as true branchiae in structure, but adapted to aerial respiration.* The North American Limneans may be said to range from the thirty-fifth to the fiftieth de- gree of north latitude; but some are found farther south, Limnea attenuata inhabiting near the city of Mexico; and a species of Physa, and one of Planorbis, near Vera Cruz. A larger number of species inhabits New England than any other part of North America of equal extent; whilst not a single species of the Melanians, own, rather than in a public conveyance, as affording better facilities for observation. In the summer of 1841, ac- companied by an assistant, and having about one hundred and fifty pounds additional weight, I drove a single horse, still in my possession, the distance of 1800 miles in forty- five consecutive days, and often over mountainous regions, and the most execrable roads, frequently breaking shafts, springs, and other portions of the vehicle, and examining every stream upon the route. * Blainville and Deshayes appear to hold the same opi- nion. PHYSAD.E. 13 and but one Paludina, has been yet observed there. They prefer quiet cold waters, species of Physa being sometimes found in springs having a temperature nearly as low as ten de- grees centigrade, and they may be sometimes seen moving along the bottom, when the sur- face is covered with ice. This fact tends to prove that they can remain a long time beneath the surface without requiring a fresh supply of air; and it is not improbable that they can remain deprived of access to the atmosphere, for several days, weeks, or even months, when the full action of their system is retarded by cold. I have observed them moving about in water at the temperature of three or four de- grees centigrade, when species of Melania and Paludina were torpid; the latter, in fact, are just able to move, in the most languid manner, in a temperature of eight or nine degrees. Like the Helicina?, this family is hermaphro- dite, both sexes being united in the same in- dividual. All the genera are oviparous, the eggs being generally deposited upon the under surface of stories, or upon sticks and leaves in the water, many being enclosed in a voluminous transparent glairy mass. This mass, in Pla- 14 PHYSAD.E. norbis, is not so large as in Physa and Limnea, and has a firmer texture. I have known the ova to become matured in two or three weeks, but the time must vary with the species and temperature. The different sub-generic sections in this family, are, probably, nearly as indicated in the following table. PHYSA. Shell reversed, mantle lobed, pi. 1. PHYSELLA, H. With branchiae, shell globose, pi. 5. APLEXA, Fleming. Lengthened, mantle simple, pi. 5. PHYSODON, H. Columella toothed, pi. 5. DIASTROPHA. Shell umbilicated, no fold. LIMNEA. Shell lengthened, pi. 5. BULIMNEA, H. Shell thick in texture, inflated, pi. 3. ACELLA, H. Shell slender, whirls very oblique. RADIX, Montf. Shell short, greatly expanded, pi. 11. AMPHIPEPLEA, Nilss. Mantle lobed. Vide LIM., p. 3. ? LEPTOLIMNEA, Sw. Nearly cylindrical, spire thick. PLANORBIS. Whirls few and regular, pi. 1. PLANORBINA, H. Whorls numerous, nearly equal. PLANORBELLA, H. Aperture campanulate, pi. 1. PLANORBULA, H. Aperture armed with teeth. SEGMENTINA, Fleming. Cavity with open partitions. ANCYLUS. Apex of the shell upon the right.* VELLETIA, Gray. Apex of the shell upon the left.* * Some authors may think it necessary to subdivide each PHYS AD.E. 1 5 ? POTAMOPHILA, Sw. "Shell resembling a Limnea, but with a distinct fold on the pillar." Mr. Swainson gives this name to certain species which he removes from Cono- vulus to place among the Limneans. Lamarck has a hypothesis touching the origin of this family,* which has induced some individuals to attack his character, by which unphilosophic means his views were to be subverted. These authors may have supposed such ideas to be unworthy of a serious refutation, apparently ignorant of the fact, that any views from so eminent a source, are worthy of the profoundest consideration of less gifted authors, who assume, rather than form their opi- nions.t Every true naturalist must thank Mr. Lyell, the distinguished British geologist, for the manner in which he has discussed this question, his essay being that of a gen- tleman, confined to the point at issue, unencumbered with considerations which have no connection with it, and pre- of these sections, into those which breathe free air, and those which oxygenate the system from water. I am of the opinion that the same species can adopt either method, according to the circumstances in which it may be placed. * Animaux sans vertebres, vol. viii. p. 378. t "If it is an obligation on science to proclaim the in- tervention of a divine power in the development of the / s*"~ whole of nature, and if it is to that power alone that we lr must ascribe all things, it is not the less incumbent on science to ascertain what is the influence which physical forces, left to themselves, exercise in all natural pheno- mena, and what is the part of direct action which we must attribute to the Supreme Being, in the revolutions to which 16 PHYSAD^E. senting a marked contrast to the vulgar, bilious effusions of such characters as a correspondent of the Entomologi- cal Magazine, who regrets that he is obliged even to cite Lamarck's works !* nature has been subjected. ... It is now time for natu- ralists to occupy themselves likewise, in their domain, in inquiring within what limits we can recognise the traces of a divine interposition, and within what limits the phe- nomena take place in consequence of a state of things im- mutably established from the beginning of creation. "Let it not be said that it is not given to man to sound these depths: the knowledge he has acquired of so many hidden mysteries in past ages, promises more and more extended revelations. It is an error to which the mind, from a natural inclination to indolence, allows itself too easily to incline, to believe impossible what would take some trouble to investigate. We generally rather prefer imposing limits to our faculties, than increasing their range by their exercise; and the history of the sciences is present to tell us, that there are few of the great truths now re- cognised, which have not been treated as chimerical and blasphemous, before they were demonstrated." rfgassiz, in Jameson's Journal, 1842. * This author's intellect appears to be sufficiently cob- webbed to enable him to apply vernacular names to shells and insects with great success; one of the methods long since invented to rob Linnaeus of the right of citation for his species. By this means he will be enabled to spare the little liberality he possesses, from the great overstrain to which he is at present compelled to submit it. The use of PHYSAD.E. 17 Mr. Charlesworth remarks, in the first volume of his Magazine of Natural History, that "Theory is often the great incentive to observation, the main stimulus to exer- tion, and the more widely those who are engaged in the prosecution of the same object differ amongst themselves as to the nature of their present conclusions, the greater, perhaps, would be the reliance which we should feel dis- posed to place in any points of common agreement that may hereafter be attained." This being admitted, I would like to see the Lamarckian hypothesis revived by some one capable of doing it justice. I furnish in these pages an additional intercalation, and consider that the Paludina subcarinata might be viewed in this connection. In this species we find a true Paludina, occasionally rounding its aperture, throwing it off from the body whirl, and not only assuming the physiognomy of Cyclostoma elegans, but actually departing so far from the normal character of its genus, as to construct a cyclostomoid opercle; that of the young animal enlarging spirally. This, however, does not continue; the animal, as a Paludina, is not endowed with the elements necessary to produce the entire opercle of a Cyclostoma, so that after continuing it to a certain point, the layers become normal, or concentric, apparently indi- cating the impossibility of a departure from its generic type, beyond a certain limit. But instead of taking this view of the shell in question, I regard it as one of the vulgar names has been carried so far, that some English authors use the word pig! instead of hog or swine; Pro- fessor Bell, however, has sufficient independence and re- spect for the language, to avoid this suiscidal course, i 3 18 strongest proofs in favor of Mr. Swainson's theory of re- presentation. There are still those who suppose scientific research, and religion, to be incompatible with each other; and who will not receive a fact in the first department, until it be ad- mitted upon competent authority in the other. Thus the theory of the solar system proposed by Laplace, was not well received until it was examined and put forth anew by Herschell.* The next great question will be (now that that of the interchange of species may be considered as settled in the negative) to account for the succession of animal forms, which the lithographic pages of geology display to our view: that is, has there been an actual modern creation, in the usual sense of the term, of all the unfossilized recent forms; or have they been called forth by laws established by Almighty power at the creation? The latter opinion will be likely to prevail, if the alleged production of a species of Acarus by galvanism, be proved to have been accomplished; nor can I see anything more impossible in the modern production of the Sarcoptes scabiei, for example, than in the recent development of a crystal. f Should this question be fairly brought before the public, some of the most bitter opponents of Lamarck, will pro- bably adopt his views in full; as some of them have done * It is difficult to conceive why the early objections to this one, should not have been turned against the theory of gravitation. f The Reverend Wm. Kirby is of the opinion that the pediculi were brought into existence subsequent to the creation of man. PHYSAD.E. 19 to a great extent, in contending that external agents have produced the different characters presented by the order Bimana. The experiment of Cross will be an experimentum crucis for the question of the mutability of species, should it be ascertained that the resulting Acarus be not produced from the egg of a known species; for it will doubtless be proven that it is not developed from an animalcule, a zoophyte, or a planarian worm. The great family of the Helicidae requires a careful study; because, from the diversity of form which it presents, it appears to offer better means than any other, towards the solution of several great physiological questions. The principle of the revolution of the spiral, in Planorbis, which results in an apex upon the same side with the obliquity of the aperture, in some species, and upon the opposite one in others, is to be discovered; and the causes of the pecu- liarities presented by the Helices, must be accounted for; such as the reversal of the aperture in Anostoma and Strophostoma, the possession or the want of teeth, and the laws which govern their production. We are at present quite ignorant of the extent to which these characters may be considered generic; and whilst one author separates Monoceros from Purpura, another unites them, because he cannot detect the peculiarity in the organization of the soft parts, which would enable him to account for the for- mation of the teeth, although the presence of the latter demonstrates the existence of the former. Chicquesalunga, October, 1842. 20 GENUS PHYSA, Draparnaud. PLATE 1. FIGS. 13. Testa convoluta, ovata vel oblonga, sinistrorsa: spira exserta: apertura longitudinalis, labrum acutum, labium in anfractum ultimum expansum. SYNONYMS AND REFERENCES. BULINUS, ADANSON. Hist. Nat. de Senegal, pi. 1, fig. G2. BULLA, LIN. GMEL. DILLWYN. PLANORBIS, MULLER. BULIMUS, BRUGUIERE, POIRET. PHYSA, DRAPARNATJD. Hist. Nat. des Moll. ter. et fluv. " LAMARCK. An. sans vert., vol. viii. p. 398. LIMNEA, SOWERBY. Genera of Shells. " SOWERBY, Jr. A Conchological Manual. DESCRIPTION. ANIMAL spiral, subglobular or lengthened: head short, flat, rounded, and emarginate in front; mouth provided with lateral lips, and a spoon-shaped tongue: foot rounded, and not much extended in front, but long and pointed posteriorly: tentacles long and slender, and swelling into an auricle at the base: eyes at the PHYSA. 21 internal base of the tentacles: inner and poste- rior edge of the mantle digitated. Organ of the deferent canal immediately behind the left ten- tacle, corresponding organ posterior to it, upon the same side, and near the pulmonary orifice. SHELL sinistral, subglobular or lengthened, smooth, and polished; with a pointed exserted spire: aperture longitudinal, with the labrum sharp, and not reflected: labium extending upon the last whirl. OBSERVATIONS. The animal is distinguished from Limnea by the digitated mantle, and setaceous tentacles; and in having the foot slender, and generally keeled, instead of oval. This organ is better adapted for locomotion than in any of the allied genera; as the animal moves about with great ease and rapidity; with a uniform, gliding mo- tion; and not by extending the foot forward, and drawing up the body. The Physse are generally less inclined to rest than the allied genera; they spend less time in a state of repose, and move about as usual, when Limnea and Planorbis are nearly torpid with cold. On the other hand, they do not 22 PHYSA. appear to suffer from a high temperature, as we find from the remarks of Mr. Lea.* When disturbed by each other, or by extraneous bodies, they whirl the shell about in such a manner as to convince the observer that it is a peculiar mode of defence. This genus was first called Bulinus by Adanson, whose name has been retained under the form Bulimus, by Bruguiere, and a few others; but Draparnaud's name pre- vails so universally at the present day, that nothing but confusion would result from a return to the first. Besides, the rule of priority, which must be so rigidly enforced with specific names, is adopted with greater latitude, when genera or families are concerned; because naturalists can- not allow the science to be tramelled here, by bad, inap- propriate, or barbarous names; although it is proper, as far as practicable, to adopt those which were first proposed. A bad specific term affects but one species, whilst an im- proper generic or family name, may affect hundreds. Adanson will have ample justice, if he be cited for Plan- orbis coretus, and Physa bulinus, simply because he re- jected the Linnean nomenclature; preferring one which he constructed with the assistance of the niggers of Senegal. An author who is not struck with the absurdity of call- ing a genus of shells apple snail, objects to such names as bobo, used by Adanson; names, however, which are not worse ih&nphyse des mousses.' or horny coil shell! * Tr. Am. Phil. Soc., vol. vi. p. 18. 23 PHYSA HETEROSTROPHA, Say. PLATE 1. PL. 2, FIGS. 1 9. P. testa ovata vel elongata, fusca vel castanea: anfrac- tibus 4 5 convexis: sutura conspicua. SYNONYMS AND REFERENCES. LISTER, Conch., pi. 135, fig. 34. SCHROTER, Einl., vol. i. p. 201, Helix no. 84. Say. LYMNEA HETEROSTROPHA, SAY. Nich. Encyc. (Am. ed. Art. Conch.) pi. i. fig. 6. Physa heterostropha, Say, Jour. Acad. Nat. Sci., vol. ii. p. 177. P. HETEROSTROPHA, GOULD. Invert, of Mass., fig. 141. PHYSA HETEROSTROPHA, DESK, in Lam., vol. viii. p. 402. BULL A FONTJNALISI INDITE ORIENTALIS, CHEMNITZ. Conch., vol. ix. pi. 103, fig. 879, 880. BULLA CRASSULA! DILLWYN. Cat., p. 487, no. 36. PHYSA AUREA, LEA. Tr. Am. Phil. Soc., vol. iv. DESCRIPTION. ANIMAL dark yellowish-grey, minutely dotted with whitish-yellow: foot, when extended, longer than the shell. When the shell is light color- ed, the animal is wine-yellow, dark yellowish- grey above, with a conspicuous spot upon each side of the forehead, made up of minute dots of 24 PHYSA HETEROSTROPHA. ochre-yellow, which cover the exposed parts. The mantle within the shell is dark brown, fre- quently spotted with light sienna, or golden- yellow, but in one variety it is black.* SHELL oval, ovate, or elongated, generally translucent, composed of four or five slightly convex whirls: suture well marked: apex point- ed: aperture narrow, longer than the spire, with the labium expanded far upon the body whirl: columella thickened. COLOR. Various shades, from light translu- cent yellowish-brown, to opaque chesnut; the outside and inside seldom presenting different shades. MONSTROSITIES. The end of the right ten- tacle furcated, and ending in two distinct points. Dr. Reinhardt. The posterior extremity of the foot divided into two unequal parts; the one on the left being the smaller, and situated late- rally. GEOGRAPHICAL DISTRIBUTION. From latitude 31 to the St. Lawrence and the great lakes; and from the North-west Territory and "Canada, * The shell of this variety cannot be distinguished from those containing light colored animals, either in shape or color. PHYSA HETEROSTROPHA. 25 to Saskatchewan." Mr. Nuttall brought speci- mens from Lewis' river, Oregon; Mr. Couper has found it on the Alatamaha, in southern Georgia; and Dr. Mighels in Maine. OBSERVATIONS. This species may be distinguished from Physa ancillaria by its greater length, darker color, and in never having a very wide aperture. I have examined hundreds from the Susquehanna, and have never found one which could be con- founded with the ancillaria, as it occurs in the Delaware; although it is difficult to decide be- tween those half-grown individuals in each, which have a wide aperture in heterostropha, and a narrow one in ancillaria; especially when those specimens of the former are chosen which have a rounded spire, as figure 8, plate 1. An extensive suite of purposely selected spe- cimens might show the propriety of uniting the two, but my present opinion is against such a step. Some elongated individuals may be con- founded with P. gyrina, but these must be con- sidered an accidental variety, as I never saw but two specimens, (figs. 6 and 7, plate 1,) which are very long, and these I collected from 26 PHYSA HETEROSTROPHA. a spring connected with the Susquehanna, which river P. gyrina does not inhabit. The posterior extremity of the labrum, is never suddenly in- curved to meet the body whirl, as in P. gyrina. I at one time believed (and described) the variety fontana as distinct, on comparing the soft parts with Tieterostropha proper, but I have since found the two gradually passing into each other. The growth of this variety is no doubt retarded by the coldness of the springs it in- habits; which causes the death, in a few days, of those brought from ponds or streams. I have noticed in a spring upon my premises, that the individuals which live upon the stones of a small ripple, are about twice the size of those upon the muddy bottom of the quiet water, two or three yards off. It must be this variety which is sometimes cited as 'P. fonti- nalis,' for the shells of the two species resemble each other very closely. The mantle, how- ever, is not as large, nor the tentacles as thick as in P. fontinalis. EXPLANATION or PLATE 1. Figure 1 represents the digitated mantle of the right side; 2, the ova; and 3, a dorsal view of the animal. 27 PHYSA ANCILLARIA, Say. PLATE 3. FIGS. 110. P. testa subglobosa, luteo-cornea; anfractibus 4 con- vexis: sutura inconspicua: spira brevi, acuta, vel erosa: apertura lata. SYNONYMS AND REFERENCES. PHYSA ANCILLARIA, SAY. Journal of the Academy of Natural Sciences of Philadelphia, vol. v. p. 124. P. ANCILLARIA, GOULD. Invert, of Mass., p. 213, fig. 142. PHYSA SAYI, TAPPAN. Am. Jour, of Science, vol. xxxv. p. 269, pi. 3, fig. 3. DESCRIPTION. SHELL subglobose, with four convex narrow whirls, of which the last is much the largest; suture nearly obliterated; apex acute, but fre- quently truncate-eroded: aperture very wide, more than twice the length of the spire: labium thick. COLOR yellowish or brownish corneous, colu- mella generally white; submargins of the aper- ture frequently reddish. MONSTROSITY. The last whirl with a square shoulder. Fig. 7. 28 PHYSA ANCILLARIA. OBSERVATIONS. "The spire of this species is unusually short, truncated at tip like the Paludina decisa, and the suture is so inconspicuous as to give rise to the name which I have chosen for it. My brother, Mr. B. Say, obtained it in the Dela- ware river near Easton, and Mr. Jessup col- lected numerous specimens in the Connecticut river above Hartford. It may be distinguished from P. heterostropha, by the shorter and trun- cated spire, inconspicuous suture, as well as by the more obtusely rounded junction of the la- brum with the base, and by the general form." Say. The very few specimens I have seen from the Connecticut river, (figs. 1 and 2,) have a more solid texture than those which inhabit the Dela- ware, (figs. 3 8,) but it is most probable that they constitute but one species. I am indebted to Mr. Anthony for the speci- men of "P. Sayi," (fig. 9,) and find it agrees in the very deep fold, and other characters, with a shell (fig. 10) from a branch of the Schuyl- kill, which I refer to P. ancillaria. PHYSA OSCULANS, Hold. PLATE 2. FIGS. 1113. P. testa ovata vel subglobosa, griseo-fusca, tenui; anfrac- tibus 5, sutura impressa: apertura lata. SYNONYMS AND REFERENCES. BULLA FONTINALIS! Indias occidentalis, CHEMNITZ, vol. ix. pi. 103, figs. 879, 880. PHYSA OSCULANS. This work, anno 1841. DESCRIPTION. SHELL allied to P. heterostropha, and pre- senting nearly the same varieties: translucent; texture very thin: lines of accretion fine: aper- ture wide, columella thick, with the fold obso- lete, or but slightly impressed. GEOGRAPHICAL DISTRIBUTION. Mexico? India? OBSERVATIONS. Specimens of this shell were presented to the Academy of Natural Sciences by Dr. M. Bur- rough; and Mexico is given as the native coun- try; but as this enterprising traveller also made collections in India, it is not impossible that 30 PHYSA CONCOLOR. they may be from the latter country. In either case, the species appears to occur in too great abundance to allow us to suppose that it is now characterized for the first time. Figure 13 is from a specimen in Dr. Jay's collection, and may be a distinct species. PHYSA CONCOLOR, Hald. PLATE 2. FIG. 10. Testa ovata; spira producta, apice acuto: anfractibus 4 convexis. DESCRIPTION. SHELL oval; spire produced, with the apex pointed: aperture oval, narrow, with the colu- mellar fold distinct. Color honey-yellow. OBSERVATIONS. Characterized from a single specimen brought from Oregon by Mr. Nuttall. 31 PHYSA FRAGILIS, MigJi. PLATE 3. FIGS. 1113. Testa ovata, pallida, tenuissima, fragili: apertura lata, repanda. SYNONYMS AND REFERENCES. PHYSA FRAGILIS, MIGHELS. Boston Jour, of Nat. Hist., vol. iv. pi. iv. fig. 12. DESCRIPTION. ANIMAL "of a very obscure, light green color; whole surface of the body covered with oblong dark spots; foot shorter than the shell, lanceo- late; tentacles nearly white, rather long, very slender; mantle blood-red." SHELL obliquely ovate, translucent, extremely fragile and delicate: suture well marked: aper- ture very wide, labium not closely appressed, and without columellar fold. GEOGRAPHICAL DISTRIBUTION. Inhabits Maine. OBSERVATIONS. Allied to P. ancillaria, but is distinguished by its greater tenuity, wider aperture, the tendency 32 PHYSA GYRINA. of the labium to grow over extraneous matter, and the want of a fold in the columella. "Its motions are exceedingly rapid; very timid, with- drawing itself on the least alarm." PHYSA GYRINA, Say. PLATE 3. FIGS. 16. P. testa elongata, castanea vel rubra: anfractibus 5 6 convexis: sutura impressa: apice acuto: apertura ovato- elongata; plica columellari obsoleta. SYNONYMS AND REFERENCES. PHYSA GYRINA, SAY. Jour. Acad. Nat. Sci., v. ii. p. 171. P. ELLIPTICA, LEA. Tr. Am. Phil. Soc. n. s., vol. v. p. 115, pi. xix. fig. 83. DESCRIPTION. SHELL oblong, polished, and translucent, with five or six convex whirls, and a well marked suture: spire gradually tapering to an acute apex: aperture more than one half the entire length, frequently thickened within the margin: columellar fold obsolete. PHYSA INTEGRA. 33 COLOR yellowish-brown to chesnut, rarely hyacinth-red. GEOGRAPHICAL DISTRIBUTION. "Inhabits the waters of the Missouri . . . near Council Bluff." Say. Mrs. Say has given me specimens from Indiana, and Mr. Anthony from Ohio. I have seen specimens from Georgia which ap- pear to belong to this species; and Professor Adams notes it as occurring rarely in Vermont. FOREIGN ANALOGUE. Physa castanea. PHYSA INTEGRA, Raid. PLATE 4. FIGS. 7, 8. P. test& ovata, pallida, subumbilicata: anfractibus 5 con- vexis, apice acuto: sutura vald impressa: plica columellari obsoleta. SYNONYMS AND REFERENCES. P. (DIASTROPHA) INTEGRA, HALD. This work, March 13th, 1841. DESCRIPTION. SHELL oval, with a lengthened, pointed spire: i 5 34 PHYSA SCALARIS. whirls five, convex: suture deep: aperture ob- tuse posteriorly, peritreme continuous; labium not appressed anteriorly, and without a fold. COLOR very pale yellowish-brown; labium, aperture, and varicose bands, white. GEOGRAPHICAL DISTRIBUTION. Sent to me from Indiana by Mrs. Say. PHYSA SCALARIS, Jay. PLATE 4. FIG. 9. Testa, ovata, anfractibus postice angulatis: spira plano- depressa. SYNONYMS AND REFERENCES. PHYSA SCALARIS^ JAY'S Catalogue, 1839, pi. 1, figs. 8, 9. DESCRIPTION. SHELL short, ovate, whirls with a distinct angulated shoulder: apex truncate-flattened: columellar fold obsolete. COLOR , . bleached. PHYSA DISTORTA. 35 OBSERVATIONS. Of this species, which occurs in Florida, I have seen but the single specimen in Dr. Jay's collection. * PHYSA DISTORTA, Bald. PLATE 5. FIGS. 1 3. P. tests, laevi, diaphana, albida perforata contorta et transversa: anfractibus 3 convexis: sutura valde impressa: apertura subrotundata. SYNONYMS AND REFERENCES. PHYSA (DIASTROPHA) DISTORTA^ HALD. This work, Oc- tober, 1840. DESCRIPTION. SHELL transverse, short, translucent and um- bilicated; composed of three very convex whirls, and having a very deep suture: spire pointed, shorter than the aperture, which is oval, and almost cyclostomous, without any fold upon the labium or columella. 36 PHYSA HYPNORUM. COLOR very light yellowish-grey. FOREIGN ANALOGUE. P. Guildingii, Sw. GEOGRAPHICAL DISTRIBUTION. Near St. Louis, Mr. Emerson: Kentucky and Ohio. OBSERVATIONS. I am indebted to G. B. Emerson, Esq., Presi- dent of the Boston Society of Natural History, for specimens of this curious shell, which were collected (by himself, I believe) near St. Louis. It is remarkable for the contorted spire, and entire absence of a columellar fold. PHYSA HYPNORUM, Lin. PLATE 5. FIGS. 4 9. Testa elongata, tenui, polita diaphana: anfractibus 5 6 planiusculis: spira subacuta. SYNONYMS AND REFERENCES. BULLA HYPNORUM, LIN. Syst. Nat., p. 1185. PHYSA HYPNORUM, DRAP. Moll., pi. 3, figs. 12, 13. " HYPNORUM, LAM. An. sans vert., v. viii. p. 400. " " Cuv. Regne An., pi. 26, figs. 5, 6. " ELONGATA, SAY. Jour. Acad., vol. ii. p. 171. PHYSA HYPNORUM. 37 JlPLEXA HYPNORUM, FLEMING. Moll. An., p. 158. JlpLEXUS HYPNORUM, GRAY'S Turton, p. 255, fig. 113. DESCRIPTION. ANIMAL "deep black, immaculate above and beneath: tentacula setaceous, a white annula- tion at base." Say. SHELL slender, translucent, and highly polish- ed; composed of five or six obliquely revolving, flattened whirls: apex apparently acute, but when closely examined, will be found to be con- vex: aperture narrow, obtusely rounded ante- riorly, acute posteriorly; labium scarcely appa- rent; columellar fold very slight. COLOR ochre-yellow, or light yellowish-brown, sometimes presenting violet and green prismatic reflexions: columella sometimes rose-coloured. GEOGRAPHICAL DISTRIBUTION. Inhabits Mas- sachusetts, Vermont, New York, and the West- ern States, "stagnant ponds on the banks of the Mississippi." Say. "Saskatchewan." Dr. Richardson. Figures 7 9 were brought from Lewis' river, Oregon, by Mr. Nuttall. OBSERVATIONS. "When the shell includes the animal, it ap- 38 PHYSA GLOBOSA. pears of a deep black color, with an obsolete testaceous spot near the base of the anterior [lower?] side. Its proportions are somewhat similar to P. hypnorum." I follow Mr. James de Carle Sowerby in re- ferring the elongata of Say to the hypnorum of Linnaeus; but, if the large variety from Oregon should prove to be a distinct species, the name elongata may be applied to it. PHYSA GLOBOSA, Hold. PLATE 5. FIGS. 1012. Testa globosa, tenui; spira abbreviate,: apertura elongata, latissima. SYNONYMS AND REFERENCES. PHYSA (PHYSELLA) GLOBOSA, HALD. Jour. Acad. Nat. Sci., vol. viii. p. 200. DESCRIPTION. SHELL globose, translucent; spire very short and rounded; aperture very long and wide, oc- PHYSA MICROSTOMA. 39 cupying considerably more than half the entire area of the shell; fold well marked: whirls three. FOREIGN ANALOGUE. Amphipeplea involuta. OBSERVATIONS. This small species inhabits the submerged rocks, in the rapids at the mouth of Nolachucky river, in Tennessee, under such circumstances as to convince me that it does not breathe the free air. I procured but two individuals, the shells of which are sufficiently translucent to exhibit light circular dots upon the black ground of the mantle; a common character in this genus. PHYSA MICROSTOMA, Bald. PLATE 4 FIGS. 1214. P. test^ crassa, laevi, pallida, elliptica; anfractibus 4 planiusculis: labio crasso; columella bidentata. SYNONYMS AND REFERENCES. PHTISA (PHVSODON) MICROSTOMA. This work, October 1840. 40 PHYSA MICROSTOMA. DESCRIPTION. SHELL elliptic, composed of four flattened whirls, separated by a distinct but very shallow suture: substance of the shell thick: spire shorter than the aperture, and ending in a point: aperture narrow elliptic, with a continuous peri- treme, and the labium much thickened anterior- ly: columella with two nacreous elevations, or obtuse teeth. COLOR light brownish-ochraceous: columella and external periodical (varicose) bands, wldte, whilst the corresponding internal bands are chesnut. GEOGRAPHICAL DISTRIBUTION. Kentucky and Ohio. OBSERVATIONS. This is a remarkable shell, and readily dis- tinguished from all the American species of Physa, hitherto described, by the teeth upon the columella. P HETEROSTROPHA.Zw. clenE.La.wson del et col AlexLaweon S: w 1_9. f HZTEROSTROPHJ, Say. 10. ^ CONCOLOR, Hald. 11_13. T 3 OSCVLAKS. Hald. 1_8. P ANCILLARIA SajS, 10. TaT. Sayi. ll._13. P FRAGILIS Migh. _6. P. CrRy-flM,.- Say. 7 8. f INTE GRA,~ Hald. 9 7? SCALjtRIS Jay. Miss Helen E Lawson del et col. l._3. P DISTORTA. 4_.9. J? HTPNORUM. L0_.12. 7? aLOBOSA. 13__15. /> , E Lam-Bou del. el col. GENUS LIMNEA, Lamarck. PLATE 1. FIG. 1. "Testa oblonga, interdiim turrita; spira exserta. Aper- tura Integra, longitudinalis. Labrum acutum, inferne ad sinistrum revertens et ascendens, in columellam versus aperturam decurrit, plicamque obliquam mentitur. Oper- culum nullum." Lamarck. SYNONYMS AND REFERENCES. HELIX, LINNAEUS. BUCCINUM, MULLER. BULIMUS, BRUGUIERES. LYMN^EA, LAMARCK. An. sans vert., vol. viii. p. 405. LYMN&US, LIMNJEUS, DRAP., TURTON, SAY, &c. LIMNEA, FLEMING, G. B. SOWERBY, Jr., etc. STAGNICOLA, LEACH. Mollusc., p. 141 145. (Gray.) CTJVIER. Mem. pour servir. a 1'Hist. et a 1'Anat. des Mollusques. Le Regne Animal, Mollusques, p. 71. SOWERBY. Genera of Shells. PENNY CYCLOPAEDIA, vol. xiii. p. 500. DESCRIPTION. ANIMAL spiral; elongated or subglobular: head depressed on each side; bearing two flat- tened, triangular, elongated tentacles; with the eyes at their anterior internal base: mouth 3 I xJ LIMNEA. surmounted by a free, thin, and movable ap- pendage: mantle simple: foot thin, oval, not extended anteriorly, and shorter than the shell: pulmonary orifice opening upon the right side, 'and near it the oviduct, whilst the organ of the deferent canal is situated near the right tenta- cle.' The sexes are united in the same indi- vidual. SHELL thin in texture, oval or elongated, surface smooth; spire exserted, tapering to a point more or less acute: aperture longer than wide, peristome incontinuous, the labrum turn- ing and entering the aperture anteriorly, form- ing a single oblique fold upon the columella. EXAMPLE. Limnea catascopium. OBSERVATIONS. The shell can be most readily distinguished from Physa by being dextral; from Succinea by the fold upon the columella, which is want- ing in the latter genus; and from Amphipeplea by the solider texture and more elongated form of the shell. The ova resemble those of Physa, except that the latter are deposited in a semi- circular, and those of Limnea, in a linear mass. This distinction I have observed in several species, but it may not be universal. LIMNEA. 3 The principal part of their food is contained in the slimy matter which covers sticks and stones beneath the water, and in the mud, which is constantly found in the intestines. Doctor Gould informs me that towards the end of the warm season, he has seen the Limnese eating each other's shells, and as Mr. Jeffreys has given the same account,* it is most probably correct; although Mr. Gray appears to doubt the fact, because the apex is sometimes deciduous, from a different cause.t The genus Amphipeplea of Nilsson, unites Limnea and Physa by characters common to both, so that its situation is difficult to deter- mine. It has the following characters in com- mon with LIMNEA. PHYSA. Shell dextral. Shell short. Tentacles triangular. A lobed mantle. If the foot is short and oval, I would place it under Limnea; if slender, and extended pos- teriorly, it belongs to Physa, where I place it * Gray's ed. of Turton's Manual, p. 231. London, 1840. } To avoid unnecessary repetition under each genus, an expla- nation of this circumstance, as well as of others appertaining equally to all the genera, will be found in the Introduction. LIMNEA. for the present. We know of no American species. Dr. Sharpey suggests that the broad tenta- cles in the genus Limnea may be instrumental in aquatic respiration, as they are provided with cilia;* these, however, are not found upon the tentacles alone, as I have observed them upon the edges of the mantle and foot, and even upon the sole of the latter; moreover, they are not confined to the Limneans; the mantle and foot (but not the tentacles) of Melania, being similarly supplied. I had thought that the long and slender tentacles of Physa might be, in part, organs of scent;t and that the ciliary currents are necessary to make them acquaint- ed with the locality of their food, the aroma of which could not well spread through the quiet waters they inhabit but the genus Amnicola, which does not generally inhabit stagnant waters, has slender ciliated tentacles also.J * Cyclopaedia of Anat., art. CILIA, vol. i. p. 621. j" Cuvier, Regne Animal Moll., p. 46. -$. In discussing this question, it should be borne in mind, that the oxygenation of the system through the external surface, has been effected in frogs, which have been confined under water for the purpose of making the experiment. In this case, however, the water may find its way to the lungs. LIMNEA. The tongue of the Limneans is almost con- tinually employed in the apparent office of taking food, as may be readily observed when the animal floats with the foot and mouth up- wards. I have, on such occasions (in Physa heterostropha) observed bits of matter to be swallowed, and have found the water to be full of Volvox globator, and other Protozoa, which are probably brought within reach by the ciliary currents. The following subgenera are indicated without any re- ference to the question of their correctness. The number happens to be five, as in Planorbis and Physa; but in the lower classes, they probably much exceed this number. The number five generally obtains, because, in genera, a greater number of distinct forms would tend to run the sections into each other; and not because Nature calls for a particular number. Still, as strong arguments have been brought forward in support of a quinary arrangement, I think it but fair that naturalists should give it an impartial and unprejudiced examination, in their peculiar depart- ments. Subgenera of LIMNEA. LIMNEA, LAM. Shell lengthened, aperture slightly ex- panded. L. appressa, pi. 5. RADIX, MONTFORT. Shell short, greatly expanded. R. raacrostoma, pi. 11. 6 LIMNEA CATASCOPIUM. ? LEPTOLIMNEA, Sw. Nearly cylindrical; spire thick, lengthened; aperture small. L. elongata. Sow. gen. fig. 6. BULIMNEA, HAL. Shell thick in texture, inflated, lip not expanded. B. megasoma, pi. 3, fig. 1 3. JlcELLA, HAL. Shell slender, whirls very oblique, aper- ture expanded. Probably the same as Leptolimnea. A. gracilis, Jay's catalogue, pi. 1, fig. 10. LIMNEA CATASCOPIUM, Say. PLATE 1. L. testa conica, tenui, ochracea; anfractibus quinis convexis: suturii excavata, spira acuta: ultimo anfractu ventricoso, apertura ovata. SYNONYMS AND REFERENCES. L. CATASCOPIUM) SAY. Nich. Encyc. (Am. ed.) art. Conch., pi. ii. fig. 3. Am. Conchology, pi. Iv. fig. 2. L. PiNGUisI SAY. Jour. Acad. Nat. Sci., vol. ii. p. 123. L. CORNEA, VAL. Rec. d'Obs. de Zoologie, &c., par Humboldt et Bonpland, vol. ii. p. 251. L. VIRGINIANAI LAM., vol. viii. p. 411. DESK. Encyc. meth. vers., vol. ii. p. 362, No. 21. L. GATASCOPIUM, GOULD. Invert, of Mass., 223. LIMNEA CATASCOPIUM. 7 DESCRIPTION. ANIMAL light or dark yellowish-brown, mi- nutely sprinkled with light yellowish: tentacles short, translucent, and light colored at their anterior base: foot about as long as the aper- ture, rounded posteriorly, with the base very minutely and thickly dotted. SHELL smooth and polished; composed of four or five convex whirls, in which the lines of growth are lightly marked; body whirl large and ventricose: suture well marked; spire shorter than the aperture; tapering to an acute point: aperture ovate: labium concave, with the fold well marked. VARIETY, L. PINGUIS. "Shell oval, rather ven- tricose, pale dirty yellowish: whirls nearly four, rapidly diminishing to the apex, which is dull fulvous: suture moderate: spire rather more than half the length of the aperture: aperture large: labrum with the inner submargin a little thickened." Say. COLOR of the outside ochre yellow 7 , but fre- quently covered with a coating of black foreign matter: inside sienna yellow. FOREIGN ANALOGUE. Limnea peregra, Drap. 8 LIMNEA CATASCOPIUM. GEOGRAPHICAL DISTRIBUTION. Inhabits Mas- sachusetts, Earle's catalogue: New York, near Niagara Falls, Dr. W. Blanding: the Hudson, Dr. Gould: the Northwest Territory, Mr. Tay- lor: from 'Canada to Saskatchewan:' and the Delaware. VAR. L. PINGUIS. The Northwest Territory, (fig. 9, Mr. R. C. Taylor,) and the Delaware (fig. 810,) and Schuylkill rivers. Mr. Nut- tall has given me specimens from Lewis' river, Oregon; which, though considerably larger, appear to belong to this variety. OBSERVATIONS. I have thought it best to unite two of Say's proposed species, for the separation of which I think there are not sufficient grounds. My suite of specimens is not sufficiently extensive to demonstrate the identity of the two; but I think the original shells of my figures 6 and 10 12, have too near a resemblance to allow them to be separated as distinct species. The variety differs in having a shorter spire, and the turns composing it more inflated; whilst the apex is not as much attenuated as in L. catascopium. LIMNEA CATASCOPIUM. The animals of figs. 1 and 6 were taken from the Delaware at Camden, and are thickly covered with Cercaria bilineata, Hald.; a para- site which must be very annoying, when pre- sent in such numbers, as in this instance. "It is with much hesitation that we adopt a new specific name for this shell (L. catas- copium), having always heretofore considered it as the same with L. putris of Europe; as far as we can ascertain, the principal difference appears to be in the more oblique revolution of the whirls in the European species, and the more abrupt termination of the spire." Say. The area of the aperture is not as great, nor is the labium as much expanded, as in the analogue. EXPLANATION OF PLATE 1. Figure 1 represents the animal at the moment of open- ing the branchial cavity, to take in a supply of fresh air. Figures 1 to 9 represent different forms of L. catas- copium, as restricted by Say; the specimens being all from the Delaware, except those of 4 and 5; the latter is a profile outline of the left side, showing the depth of the umbilical emargination: 8, 9 show the form of the young: and 10, 11, 12 represent the variety L. pinguis. The foreign analogue of this species is placed under the j 2 10 LIMNEA EMARGINATA. subgenus Radix; on which account, a more characteristic species should have been given as the example (as L. jugularis;) but there might be some risk in citing an ani- mal which I never saw, and which might possibly possess anomalous characters. Thus the editors of the current edition of the Regne Animal, instead of following their rule of figuring none but the best known species, have de- parted from it in preferring 'Cistuda clausa' (C. Carolina) a land animal, instead of figuring Terrapene Europsea, in illustration of the text: "On doit remarquer parmi les tortues d'eau douce, les tortues a boite." A little caution, in the study of the Mollusca, cannot be misplaced; when authors like Cuvier and Duvernoy have confounded the Testudininae with the Emydae, by placing too much con- fidence in the character of the shells. LIMNEA EMARGINATA, Say. PLATE 2. L. testa tenui, subdiaphana, anfractibus quaternis vel quinis convexis, ultimo maximo: sutura valde impressa: apice acuto: crena columellari profunde emarginata. SYNONYMS AND REFERENCES. LIMNEUS EMARGINATUS, SAY. Journ. Acad. Nat. Sci., vol. ii. p. 270. American Conchology, pi. 55, fig. 1. LIMNEA EMARGINATA. 11 DESCRIPTION. SHELL ovate-conic, thin in texture, translu- cent, and smooth; having the lines of growth very fine: there are five whirls, which are very convex, and are separated by a deep suture: apex, when present, acute: aperture wide, and more than half the entire length: labium turned over, so as to form an umbilic: fold on the columella obsolete: colurnellar depression deep- ly emarginate. COLOR light ochraceous. GEOGRAPHICAL DISTRIBUTION. Inhabits "lake Namakin, north of lake Superior" Say: lakes in the North-west Territory, Mr. Taylor: and the State of Maine, Dr. Gould. OBSERVATIONS. "This species is rather larger, and consider- ably wider than L. catascopium; and the emar- gination visible on a profile view of the um- bilical groove, is far more profound." Say. Specimens are not common in collections, so that it is difficult to define the limits of the species. Thus figure 1 differs considerably from figure 6, but they both agree in having a 12 LIMNEA EMARGINATA. deep emargination, as exhibited in figures 3 and 7 in wanting the fold upon the columella, and in having umbilics of the same character. Should the latter prove to be a distinct species, I propose to call it L. serrata; its distinguish- ing characters being the elevated lines, and the undulated peritreme. It is probably included by J. D. C. Sowerby among the new species discovered by Dr. Richardson. EXPLANATION OF PLATE 2. Figures 4 and 5 are copied from an authentic specimen in the Academy's collection: 1,2, 3, represent a more elon- gated variety, drawn from an imperfect specimen; and 6, 7, 8, a shell which is more ventricose, and is marked with a few transverse elevated lines upon the body whirl. These two shells, with many other species, were brought from the North-west Territory by Mr. R. C. Taylor, who gave them to Mr. Conrad; to whom I am indebted for the freshwater univalves contained among them. 13 LIMNEA MEGASOMA, Say. PLATE 3. FIG. 13. L. testa maxima, inflata, rufa; spira acuta, non longitude aperturae habente: anfractibus quinis convexis: sutura impressa, apertura subovata; columella alba, profunde plicata. SYNONYMS AND REFERENCES. LYMNEUS MEGASOMUS, SAY. Long's Expedition to the source of St. Peter's river, &c., vol. ii. p. 263, pi. xv. fig. 10. DESCRIPTION. ANIMAL blackish, Binney. SHELL very large, oval, inflated, and rather solid; composed of five convex whirls: the lines of growth are coarse, crossed by very fine, and almost obsolete, transverse lines: suture deep: spire short, and frequently much eroded, in large shells: aperture oblong ovate, capacious: fold on the columella well marked. COLOR of the shell, yellowish-brown; within, reddish-brown. GEOGRAPHICAL DISTRIBUTION. Found in the North-west Territory, Say: (north latitude 14 LIMNEA MEGASOMA. 48) and collected by Dr. Binney "in a swamp in front of the town of Burlington, Vermont, very near the shore of Lake Champlain." OBSERVATIONS. "This remarkably large and fine species was found in Bois blanc Lake, North-west Territory, by Dr. Bigsby, to whom I am indebted for specimens. The color is brownish, sometimes lineated across the body whorl with dull green- ish and pale ochraceous; and the chesnut- brown color of the interior of the shell, com- bined with its large dimensions, distinguish this species from all others yet discovered in this country." Say. The shell of this species is rare in collections, and I am indebted to the liberality of Dr. A. Binney of Boston, for the only specimens in his cabinet. The shell reminds one of the young of Plekocheilus undulatus, Guilding. The N. W. Territory must be the original station of this species; whence it has reached a distance of 1,500 miles, with the descending waters. The more rapid current of the Mis- sissippi, and the difference in climate, have doubtless prevented it from establishing itself in the Western States. 15 LIMNEA RUGOSA, Val. PLATE 3. FIG. 4 5. L. "testa ovato-conica, tenui, alba, tsenia fulva obsoleta ornata; anfractibus rugis plurimis exaratis." Valenc. SYNONYMS AND REFERENCES. LYMNEA RUGOSA, VALENCIENNES. Receuil d'Obs. de Zoologie, etc., par Humboldt et Bonpland, vol. ii. p. 250, pi. Ivi. fig. 5, a, b. An. 1833. DESCRIPTION. SHELL ovate-conic, thin, composed of six convex whirls, upon the later ones of which, the lines of accretion are very coarse: aperture elliptic, longer than the spire, columella reflect- ed upon the last whirl, so as to form a small umbilic. COLOR white, with a transverse spiral fulvous band. GEOGRAPHICAL DISTRIBUTION. Mexico. OBSERVATIONS. This species was discovered by M. Bonpland in Mexico. My figures and description are taken from the work cited. 16 LIMNEA JUGULARIS, Say. PLATE 4. L. testa magna, ovato-conica, Isevi, tenui, pellucida: spira elongata, attenuata, apice subacuto: anfractibus longitudinaliter minutissime striatis: ultimo anfractu ven- tricoso: columella profunde plicata. SYNONYMS AND REFERENCES. L. JUGULARIS, SAY. Nich. Encyc. Art. Conchology. L. SPECIOSUS, ROSSMASLER, pi. 2, fig. 50. L. STAGNALIS, Am. Jour, of Sci., vol. xxxi. p. 36. note f. DESCRIPTION. SHELL large, thin, ventricose, smooth, and diaphanous, composed of six slightly convex whirls, of which the lines of growth are very fine: spire contracted and subulate, with the apex pointed: aperture large, inner side sub- rectilinear, outer margin slightly expanded: columella with a deep fold: there is no umbilic, the labium being in close contact with the last whirl. COLOR light ochre yellow. LIMNEA JUGULARIS. 17 GEOGRAPHICAL DISTRIBUTION. Lakes in New York, Michigan, North-west Territory, (fig. 2.) and Lewis's river, Oregon, (fig. 1.) OBSERVATIONS. The shell of this species bears a very close resemblance to that of L. stagnalis, but may be distinguished by the want of the prominent shoulder to the whirls, which is so conspicuous in that species. A single monstrous individual, presented to Academy's collection by Mr. Nuttall, has, however, a well developed shoulder. The surface of Stagnalis has a tendency to form facets, which is not the case with Jugu- laris; nor has it the spiral striae quite as evi- dent; a character still better developed in L. appressa. The revolution of the edge of the columella leaves a conical open axis, of about equal size in both species (but narrower in L. appressa) which admits of a view far into the shell. Both species agree remarkably well in the colour, texture, and translucency of the shells. j 3 18 LIMNEA APPRESSA, Say. PLATE 5. L. testa magna, elongata, pallida, tenui, laevi, transver- sim minutissime striata, apice subacuto: anfractibus 6, subconvexis: apertura ovata. SYNONYMS AND REFERENCES. LYMNEUS APPRESSUS, SAY. Jour. Acad. Nat. Sci., vol. ii. p. 168. L. spEciosuSj ZEIGL., ROSSMJESSLER, Iconog., pi. 2, fig. 50. DESCRIPTION. "SHELL elongated ventricose: volutions 6: spire regularly attenuated to an acute tip, rather shorter than the aperture: body whirl dilated, proportionally large: aperture ample, columella with the sinus of the fold profound; callus perfectly appressed upon the shell, to the base." Say. COLOR, pale ochraceous, lighter than the pre- ceding species, and frequently stained by a black foreign matter. LIMNEA APPRESSA. 19 GEOGRAPHICAL DISTRIBUTION. From Lake Superior to New England, inclusive. The specimens figured were given to me by Dr. Binney, who procured them at Burlington, Vermont. OBSERVATIONS. I am not very confident that this is distinct from the preceding species; but admit it, be- cause it is more attenuated, lighter in color, and has the spiral striae better developed. I cited Rossmassler's figure under the pre- ceding species, on the strength of Gray's Tur- ton; but I am now able (through the kindness of my friend Dr. Gould) to cite at once from the work itself; which convinces me that Ross- massler had this species in view, as his figure and minute description agree with it in every particular. 20 LIMNEA FRAGILIS, Lin. PLATE 6. L. testa conica, acuminata, sub-perforata; irregulariter reticulata, et transversim minutissime striata: anfractibus 6 7 convexis: sutura impressa. SYNONYMS AND REFERENCES. HELIX FRAGILIS, LIN. BUCCINUM PALUSTRE, MULLER. LIMNEUS E LODES, SAY. Journal of the Academy of Natural Sciences, vol. ii. p. 169. American Con- chology, pi. 31, fig. 3, March 1832. L. PALUSTRIS, J. D. C. SOWERBY'S Catalogue of Dr. Richardson's Shells, No. 32. LIMNJEA E LODES, GOULD. Invertebrata of Massachusetts, p. 221, figs. 146, 147. DESHAYE'S LAMARCK, vol. viii. p. 409. DESCRIPTION. ANIMAL fuliginous, minutely dotted with wax- yellow: central portion dark above; color near- ly uniform below: foot elliptical, about two- thirds the length of the body whirl when extended: tongue spoon-shaped, mouth mar- gined in front with a black horny plate or tooth. Gould. LIMNEA FRAGILIS. 21 SHELL oblong-conic, slightly umbilicated, composed of six convex whirls, the surface of which is frequently marked with irregular ele- vated reticulations, unconnected with the fine lines of growth, or the very minute spiral lines: suture very distinct, but not deep: aperture generally shorter than the spire, and sometimes having a calcareous rim within the peristome. The characteristic shell has the irregular elevated lines, and convex whirls, as figure 1. The varieties are as follow: A. Smooth, whirls convex, fig. 3. B. Smooth, whirls flattened, figs. 4 and 11. C. Color dark, aperture irregular, fig. 6. D. Color light, aperture margined, fig. 7. E. Aperture simple, color dark brown, fig. 9. The varieties D and E have the minute spiral lines very distinctly marked, but the irregular reticulations are wanting: when these are pre- sent, the surface is divided into series of facets, which have been compared to those upon cut- glass. COLOR various shades of brown and yellow- ish-brown, aperture frequently margined with chesnut. GEOGRAPHICAL DISTRIBUTION. Found in the 22 LIMNEA FRAGILIS. North-west Territory; Canada, as far north as Great Bear Lake, and Maine: in Massachu- setts, figs. 2, 6, 8, Dr. Gould: New York and Lake Erie, fig. 9: Ohio, figs. 1 and 7: Eastern Pennsylvania, figs. 3, 4, 10, 11, from a spring in Berks county, connected with the Schuylkill. I have a specimen H inches long, and rather more than half an inch in diameter, from Lewis' river, Oregon, which I refer to this species, although it is more ventricose than the indi- viduals we are accustomed to see. OBSERVATIONS. I am indebted to Dr. Gould (who has given an interesting account of this species), for the description and drawings of the animal. Figure 5 will give those who are not acquainted with the animals of this family, an idea of the form of the head and tentacles. Say remarks that his elodes "bears the most striking resemblance to L. palustris of Europe, and I am almost inclined to think it a mere variety of that species." I unite the two, be- cause I am unable to point out any distinguish- ing characters between them. Whether the foreign shells are as variable among themselves LIMNEA FRAGILIS. 23 as ours are, I cannot tell; but I have specimens which, if found here, would be named elodes without hesitation. The respective soft parts may differ; but until such a difference be point- ed out, I cannot but consider the two identical; nor can I admit doubtful species, or those nearly allied to others, upon a mere (so called) specific character, unless a comparative character be given at the same time. Surely it is not unreasonable to demand that enough be given to convey an idea of proposed species, which, in many cases, are difficult to identify, even from figures. Mr. Gray is of opinion that the calcareous rim within the peristome of certain Limneae and Planorbes, is formed when the waters they inhabit are nearly dried up; or in winter, when they are affected by cold preparatory to the secretion of a diaphragm for their protection at these times.* However this may be, I have never observed the rim in any other of our species, and only in variety D. of this, whose appearance will always distinguish it, even when this character is wanting. This variety has not been hitherto observed east of the Allegany Mountains. * Turton's Manual, p. 231 and 267. London, 1840. 24 LIMNEA UMBROSA, Say. PLATE 7. L. testa elongata, ventricosa, fusca: spira attenuata, acuta: anfractibus senis, convexiusculis, transversim minu- tissime striatis: apertura semicirculari; labro repando. SYNONYMS AND REFERENCES. LIMNEUS ELONGATUS, SAY. Journ. Acad. Nat. Sci., vol. ii. p. 167. LIMN E us UMBROSUS, SAY. Amer. Conchology, pi. 31. fig. 1. DESCRIPTION. Shell lengthened, ventricose, composed of six slightly convex whirls, of which the anterior one is somewhat inflated: surface covered with numerous minute transverse spiral lines: suture oblique, with little depth, but well marked: spire attenuated, with the apex acute: fold on the columella not well marked: aperture wide, nearly straight on the inside, wide anteriorly; less than half the length of the shell: body whirl above, longer than half the entire length. LIMNEA UMBROSA. 25 COLOR various shades of brown, or reddish- brown; sometimes with light longitudinal lines, as in figue 6: the submargin of the peristome is frequently chesnut. GEOGRAPHICAL DISTRIBUTION. "It inhabits, in considerable numbers, the ponds and tranquil waters of the Missouri, in the vicinity of Council Bluff; and Dr. Bigsby obtained specimens in Rainy lake and Seine river of Upper Canada." Found in New York, Ohio, Indiana, and Illi- nois. OBSERVATIONS. This shell is more ventricose than in any of the allied species, and the fold upon the colu- mella is liable to considerable variation, being well marked in some individuals, and nearly obsolete in others. In some shells the apex is much elevated (the shell being in the normal position) because the plane of the aperture forms a large angle with the axis. Figures 2 and 7 represent this character largely de- veloped. The name first given to this species by Say was preoccupied, which led him to redescribe it under the one by which it has since been known. j 4 26 LIMNEA REFLEXA, Say. PLATE 8. L. testa elongata, tenui, fusca; longitudinaliter striata: apice acuto: anfractibus 7 convexiusculis: sutura impressa, obliquissima: apertura elongata: lamina columellari crassa et laxa. SYNONYMS AND REFERENCES. LIMNEUS REFLEXUS, SAY. Jour. Acad. Nat. Sci., vol. ii. p. 167. American Conchology, pi. 31, fig. 2. LIMNEA PALUSTRIS, var. distortus, ROSSMASSLER. Icon., vol. i. p. 97. LYMN^EA EXILIS, LEA. Tr. Am. Phil. Soc. (new series), vol. v. p. 114, pi. xix. fig. 82. DESCRIPTION. SHELL very long and slender, composed of seven flattened, or slightly convex whirls, with exceedingly minute transverse revolving lines: lines of growth distinct, but sometimes very fine: suture well marked, revolving very obliquely: aperture oblong semicircular; columellar fold slight; labium not quite in contact with the body whirl at any part, particularly anteriorly, where there is a slight umbilical fissure. LIMNEA REFLEXA. 27 COLOR fulvous, or brownish-ochraceous; the inner submargin being frequently highly colored with reddish-brown. GEOGRAPHICAL DISTRIBUTION. Found in Supe- rior and Erie Lakes, Say: in Ohio, Indiana, Illinois, and New York. OBSERVATIONS. This and the preceding species vary consi- derably among themselves; and occasionally approach each other in such a manner, that it is possible they may be but varieties, however characteristic specimens (as figure 1 of the respective plates) may differ. I believe them to be distinct; as, besides the general form, the columellar fold is better marked in L. umbrosa, and the labium is in contact with the preceding whirl. Mr. Lea gives the want of appression in the labium as the distinctive character of his L. exilis; but this character is present in all the specimens figured upon plate 8, except the young, figs. 7, 8. I am indebted to Messrs. Anthony, Conrad, and Olmstead, for placing the specimens figured, in my collection. 28 LIMNEA ATTENUATA, Say. PLATE 9. FIGS. 15. L. test elongata, tenuissima, diaphana, fragili, acuta: anfractibus 7 planulatis: sutura impressa, obliqua: aper- tura semicirculari; plica columellari impressa. SYNONYMS AND REFERENCES. LIMNEUS ATTENUATUS, SAY. Disseminator, p. 244, Aug. 12th, 1829. Mrs. Say's reprint, p. 23. DESCRIPTION. SHELL very long and slender, with seven slightly convex whirls, revolving obliquely: suture rather deep: apex suddenly pointed: aperture small and semicircular, sometimes expanded: columellar plait well marked. The young shell does not differ materially from the adult. COLOR wood-brown. GEOGRAPHICAL DISTRIBUTION. Found by Say in the ditches and ponds about the city of Mexico. LIMNEA EXPANSA. 29 OBSERVATIONS. " This species is more nearly related to L. reflexus, Nob., than to any other known species of North America; but it is only necessary to compare the two, in order to perceive a wide difference between them. The present is smaller and proportionally more slender, and the spire is more attenuated." Say. LIMNEA EXPANSA, Hold. PLATE 9. FIGS. 6 8. L. test^ inflato-conica, tenui, brevi, diaphana: aperlura lata, labro repando: plica columellari profunda. SYNONYMS AND REFERENCES. L. EXPANSA, HALD. In this work, October, 1840. DESCRIPTION. SHELL short, smooth, translucent, and fragile; body whirl inflated: spire as long as the aper- ture, and rapidly attenuated to an acute apex: 30 LIMNEA EXPANSA. whirls five, somewhat flattened: suture shallow, but very distinct, aperture effuse: fold on the columella deep and distinct. COLOR brownish ochre-yellow. GEOGRAPHICAL DISTRIBUTION. Found only in Vermont. OBSERVATIONS. I owe the opportunity to describe this new species to Dr. Gould, who gave me specimens, and the information that they are from Ver- mont. It differs from L. elodes in having a polished surface, expanded aperture, obsolete lines of growth, translucency, and a deeper fold upon the columella. It cannot be con- founded with any other species. 31 LIMNEA DESIDIOSA, Say. PLATE 10. L. testa sub-inflata, perforata, tenui, lutea: spira at- tenuata, apice acuto: anfractibus 5 convexis: sutura valde impressa. SYNONYMS AND REFERENCES. LIMNEUS DESIDIOSUS, SAY. Jour. Acad. Nat. Sci., vol. ii. p. 169. Am. Conch., pi. 55, fig. 3. L. OBRUSSA 1 SAY. Jour. Acad. Nat. Sci., vol. v. p. 123. L. ACUTA, LEA. Trans. Am. Phil. Soc., (new series,) vol. v. pi. 19, fig. 81. L. PHILADELPHIA, LEA. ib. Proceedings, vol. ii. p. 32. DESCRIPTION. ANIMAL with the foot as long as the two last whirls: tentacles short, broad, and translucent: color light yellowish-grey, dark upon the mid- dle and light upon the edges: surface minutely dotted with whitish, which forms spots between the eyes. SHELL somewhat inflated, thin in texture, and translucent: lines of accretion rather coarse: surface occasionally broken by a tendency to 32 LIMNEA DESIDIOSA. form irregular facets: spire about as long as the aperture, and rapidly attenuated to an acute point: there are five convex whirls, sepa- rated by a deep suture: body whirl much the largest: aperture wide, generally obtuse poste- riorly; peristome nearly level: labium thick and not appressed anteriorly: colurnellar fold slight, or wanting. COLOR light ochraceous, sometimes brownish: polished within; and occasionally white na- creous, or pink, anteriorly. GEOGRAPHICAL DISTRIBUTION. From latitude 35 to 45, and from New England inclusive to the Mississippi; inhabiting rivulets and small lakes in great abundance. OBSERVATIONS. This species is subject to great variation in the form of the shell, but the animals of the slender and the ventricose varieties cannot be distinguished; and the shells approach each other by insensible gradations, as I have ascertained from the examination of several hundred specimens, many of them whilst living. Those represented by figures 1, 4, 5, 6, 7, 8, 9, are from a pond of spring water twenty feet in LIMNEA DESIDIOSA. 33 diameter and two feet deep, on the Susquehan- na, near my residence. It is subject to desic- cation in very dry seasons, and has a bottom of mud, and but little vegetation, which is chiefly confervoid. The soil is slightly cal- careous. I am thus particular, because this pond appears very favourably adapted to the growth of these animals, as well as Physa heterostropha and Planorbis bicarinatus. I have never found but the single specimens with as short a spire, or as wide an aperture, respectively, as those represented by 5 and 7. Having received specimens of his 'L. acuta,' fig. 14, and 'Philadelphia,' fig. 10, from Mr. Lea, I have no hesitation in referring them to this species, to which his L. casta probably belongs also. EXPLANATION OF PLATE 10. The shells figured are all Pennsylvanian. Figures 2 and 3 represent specimens from Tuscarora creek, and may be assumed as good examples of the species; 10 and 12 from near Philadelphia; 11, 13, 15, from near my resi- dence; and 12, from the gutters along the road above Columbia. The last bears a very close resemblance to Say's obrussa, but I cannot, with certainty, refer the latter to the species under consideration, because I have not a sufficient number of authentic specimens for comparison. K 5 34 LIMNEA CAPERATA, Say. PLATE 11. FIGS. 19. L. testa conica, anfractibus 5 6 convexis, transversim minutissime striatis: apice acuto: sutura valde impressa: apertura ovata. SYNONYMS AND REFERENCES. LYMNEUS CAPERATUS, SAY. Disseminator, p. 230, July 29th, 1829. Mrs. Say's reprint, p. 23. L. UMBILICATA, ADAMS. Boston Journ. Nat. Hist., vol. iii. p. 325, pi. iii., fig. 14. L. UMBILICATA, GOULD. Invert, of Mass., p. 218, fig. 149. DESCRIPTION. ANIMAL dark colored, approaching to black, very minutely and sparsely dotted with whitish, which is scarcely perceptible, except between the eyes: tentacles long and very flat: foot as long as the aperture and adjoining whirl, rounded posteriorly: in the young, light spots are sometimes visible through the shell. SHELL conic, composed of five or six convex turns, separated by a deep suture: apex point- ed, and entire: lines of growth fine, but appa- LIMNEA CAPERATA. 35 rent: surface closely covered with numerous and very fine spiral, light-colored, elevated, epidermal lines; which are quite distinct upon the young or half-grown, but obsolete upon the adult shell: aperture ovate, semicircular, or subrotund: labium apparent, with scarcely any fold; and separated from the basal whirl ante- riorly, so as to form a more or less distinct umbilic. COLOR yellowish-brown, sometimes marked with whitish or reddish varicose bands: aper- ture frequently stained with reddish-brown. GEOGRAPHICAL DISTRIBUTION. Prof. Adams has sent me specimens from Vermont, and 'L. umbilicata' from New Bedford: Mrs. Say from the Wabash: Dr. Wm. Blanding from Illinois: Mr. Anthony from Ohio: and I have found it in eastern Pennsylvania. OBSERVATIONS. Two of the characters given by Say to this shell "spire half the length of the mouth .... suture not very deeply impressed" do not apply to any of seventy or eighty specimens now before me; all of which have a well mark- ed suture, the spire equalling the length of the 36 LIMNEA SOLIDA. aperture, but in most cases longer, and rarely shorter. There is, however, little doubt about these being the caperata, as they agree with most of the characters given, and especially with the description of the revolving lines. These are so superficial, as to be readily re- moved with a brush. EXPLANATION OF PLATE 11. Figures 1, 2, 4, 6, 7, 8, are from specimens collected from a spring of shallow running water, subject to being dried up, and flowing into the Susquehanna at Marietta, Pennsylvania-. The bottom is a deep bed of black tena- cious mud, covered with grass. Mr. Adams' specimens are from a somewhat similar locality. Figure 3 is from an Illinois specimen; 5 from a Vermont shell; whilst 9 represents 'L. umbilicata.' LIMNEA SOLIDA, Lea. PLATE 11. FIGS. 1013. L. testa conica, laevi, subsolida, umbilicata; apice acuto: anfractibus 4 5 convexis, sutura excavata: apertura sub- ovata, decolorata. LIMNEA SOLIDA. 37 SYNONYMS AND REFERENCES. Z. SOLIDA, LEA. 7 Tr. Am. Phil. Soc., vol. vi. p. 94 and L. APICINA, " 3 102, pi. 23, fig. 91. DESCRIPTION. SHELL obtusely conical, smooth, and umbili- cated; with four or five convex whirls, separated by a deep suture: apex pointed: aperture polish- ed, subovate, with the fold conspicuous when young, and obsolete in the adult. COLOR pale bluish-grey, apex and aperture various shades of reddish-brown: young ochra- ceous. GEOGRAPHICAL DISTRIBUTION. Found by Mr. Nuttall near the mouth of Wallamut river, Oregon. OBSERVATIONS. As Mr. Lea's figures 91 and 94, (the latter purporting to be 'L. apicina,') are too distinct to represent the same shell, it becomes neces- sary to give my reasons for not admitting the latter as a species. These are, the fact that my figures represent but one species: the infor- mation from Mr. Lea that the shells figs. 11 38 LIMNEA COLUMELLA. and 12 are 'L. apicina,' the perfect agreement of the former shell (fig. 11) with the descrip- tion and remarks, and the tolerable resemblance to the figure of L. solida, and of the shell fig. 12, with the description of 'L. apicina;' lastly, an examination of his specimen of L. solida (fig. 13) afforded me by Mr. Lea. LIMNEA COLUMELLA, Say. PLATE 12. L. testa ovata, fragili, diaphana: anfractibus 4 convexis, ultimo maximo; lineis transversis minutis corrugatis: aper- tura lata. SYNONYMS AND REFERENCES. L. COLUMELLA, SAY. Nich. Encyc. (3d Amer. edit.) Lymnea, No. 3. Jour. Acad. Nat. Sci., vol. i. p. 15. L. COLUMELLA, GOULD. Invert, of Mass., p. 215, fig. 144. VAR. CHALYBEA, " Ibid. p. 216, fig. 145. L. NAVICULA, VAL., in Rec. d'Obs. de Zool. etc. par Humb. et Bonpl., vol. ii. p. 251. L. ACUMINATA, ADAMS. Am. Journ. Sci., vol. 39, p. 374. L. MACROSTOMUS, SAY. Journ. Acad. Nat. Sci., vol. ii. p. 170. LIMNEA COLUMELLA. 39 L. MACROSTOMA, GOULD. Invert, of Mass., p. 217, fig. 148. L. COARCTATA, LEA. Proceed, of Am. Phil. Soc., vol. 2, p. 33. DESCRIPTION. SHELL ventricose, ovate, fragile, thin in tex- ture, and diaphanous: suture impressed and con- spicuous: whirls 4, with the lines of accretion apparent, and crossed by minute spiral striae: spire narrow, acute, and much shorter than the aperture: aperture very large, more or less expanded; labium a thin film of enamel, not quite appressed anteriorly; peritreme extremely thin and fragile, entering the axis, and forming an open spiral, of which two or three turns are generally visible. COLOR light straw yellow, frequently tinged greenish, brown, or black, by foreign matter. GEOGRAPHICAL DISTRIBUTION. Maine, Massa- chusetts, Pennsylvania, Ohio, South Carolina, the North-west Territory, and Lake Winnipeg. FOREIGN ANALOGUE. L. ovata. OBSERVATIONS. The labium is sometimes scarcely visible, 40 LIMNEA COLUMELLA. and in this case, the shells are difficult to dis- tinguish from those of some species of Succinea. They differ very much among themselves; and, in some instances, approach L. auricularia in form. ; L. macrostoma' appears to me to be nothing more than a variety with a well ex- panded aperture; a distorted individual, in fact, (fig. 6) having been a 'columella' until it sud- denly assumed the macrostomous form in the body whirl. 'L. succiniformis,' Adams, MS., I refer to this species. Say alludes to a variety which he found in Missouri, and which, judging from its color, must be identical with the variety 'chalybea.' To be obtained in perfec- tion, this species must be sought for early in the spring. REFERENCE TO PLATE 12. Figures 13 15 represent the original 'L. columella;' 1 5 'L. macrostoma;' 9 Say. 8_1S. L. COLITMELLA, ! Plate 13 4 4 4 5 f 4 4 4 ' 1__8. Z. HUMILIS __ Say. 9__10. L. u_is. z.. rrr^ez-^, Haid. i6.._ifl. z. 21 X. GRACILIS,..^3aif. awsoi. delet col. tt. 1113. Z. ?,^. i9_20. z. 22. -23. Z. G ALB ANA. Alsx. I.awson Sc MIBS Helen Rl.awson del at col. Plate 15. GENUS PLANORBIS, Mutter. PLATE 1. FIGS. 1,2. Testa discoidea, spira valde depressa: anfractibus omni- bus utrinque conspicuis: apertura lunata, ab axe remotis- sima. SYNONYMS AND REFERENCES. HELIX, LINNAEUS, GMELIN, WOOD, &c. PLANORBIS. MULLER, BRTJGTJIERE, &c. LAMARCK. An. sans Vert., viii. p. 379. DESHAYES. In the same, viii. p. 380. Anno 1838. SOWERBY. Genera and Manual. CUVIER. An. du Mus. Memoires, Anno 1817, Regne ani- mal, pi. 26, fig. 4. DESMOULINS. Tr. Soc. Lin. Bordeaux. Anno 1831. PENNY CYCLOPAEDIA, xiii. p. 495. DESCRIPTION. ANIMAL elongated, slender, and closely rolled up; head saddle-shaped and slightly emarginate, anteriorly: tentacles long and setaceous; mouth provided with a spoon-shaped tongue, opposed to a concave tooth anterior to it; respiratory orifice upon the left side. K 1 Z PLANORBIS. SHELL an involute discoid spiral, with the turns visible on both sides; aperture lunated, modified by the penultimate whirl, and more or less oblique, causing the shell to incline towards the left: apex not confined to either side. f Apex upon the left side. P. bicarinatus. tf Apex upon the right. P. exacutus. fft Apex visible on both sides. P. deflectus. OBSERVATIONS. There has been some difference of opinion as to whether this genus is generally dextral or sinistral, and the reader is referred to the work last cited (which includes Deshayes' more important remarks) for views upon both sides of the question; but as this is not yet settled to the satisfaction of all, a few remarks will be added to what has been already written. When the animal of P. bicarinatus or P. corneus is placed so that the margin of the aperture rests horizontally, (its normal position,) the shell leans toward the left, because the right edge of the labrum is produced farther than the left,* which brings the spire to the lower, and * This view is taken by Deshayes, and is the correct one; as any one can ascertain by examining the animal when in motion. (PI. 1, fig. 2.) PLANORBIS. 3 the umbilic to the upper side. If a dextral, dis- coid Helix (as Carocolla albella) be placed be- fore a mirror,* the reversed image will not cor- respond with a Planorbis; as, in the former genus, dextral or sinistral, the spire is invari- ably upon the right, or upper side; so that the shell of the typical section of Planorbis is anomalous, whether it be viewed as dextral or sinistral, the apex being upon the side towards which the plane of the peritreme is directed. This circumstance appears to have been hereto- fore overlooked, to which may be attributed the difference of opinion upon this question. When Sowerby asserts (from examination of the ani- mal) that Planorbis carries its shell differently from dextral genera, he must have looked at the apex alone; for in other respects, Planorbis corneus* and Helix albella correspond exactly. If the apex is to determine the question; sup- posing the animal to be deprived of its shell; how easily it might be made dextral or sinistral, by pressing the part corresponding to the apex, from side to side. Planorbis parvus, deflectus, contortus, vortex, and complanatus, have flat shells, which show the apex on both sides, * The comparison may be more easily made, by using a reversed Helix. 4 PLANORBIS. whilst in P. armigerus exacutus and Segmentina lineata, it appears only above, or on the right side, as in Helix; but all these species have the inclination of the aperture like other Planorbes, or dextral Helices; and independently of any inclination of the periphery to either side. As an additional argument in favor of the aperture deciding the question, let us suppose the apex and whirls of a very flat Helix, like Polygyra septemvolva, to be pushed through; and the heterostrophe coil will represent, not a sinistral Helix, but a reversed Anostoma; which genus resembles the typical Planorbes, in being dextral, and having the aperture and apex upon the same side. These being the facts of the case, the apex must be left out of the question; and taking the animal and aperture as our guide, we must come to the conclusion that the shell is dextral, and umbilicated above. The heart of Planorbis is placed upon the right side, and the respiratory orifice upon the left, contrary to what obtains in most pneumo- branchiate mollusca; but M. Desmoulins ascer- tained that the organs of digestion and genera- tion are situated as in dextral shells; so that the arguments drawn from the former fact, are more than counterbalanced by the latter. PLANORBIS. 5 Planorbis appears to be more nearly related to Helix, than any other genus of Physadas; in the first place, by the form of the shell, and secondly, by the dentate aperture in the subgenera Segmentina and Planorbula. Some au- thors are inclined to look upon this armature as an artificial character, only useful for specific distinction; in other words, characters, the bearings of which are not under- stood, we, in our ignorance, call artificial; and arrange- ments which take them into account, are designated by the same term, to distinguish them from natural arrangements, founded more or less upon appreciable relations.* It is certain, that the more that is known, the less is it possible to draw a line of distinction between the two assumed orders of character. We might, at first view, suppose size and color to be artificial characters; at least, as far as genera are con- cerned; yet we find Paludina composed of comparatively large individuals, and the allied genus Amnicola, of small ones. Certain uniform colors, lines, or spots, mark genera and families; in Cervus and Antilope the rump is frequently of a lighter tint than the general color; and in Cicindela, the pattern is remarkably uniform through a very large number of species. Under MELANIA, some remarks will be found upon geographical position, as indicating the genus, in certain cases where species present anomalous or osculating generic characters. * Methodus artificialis exceptionum quidem immunis esse potest, quia ex unitate principii divisionis derivatur; sed systema naturale exceptionibus necessario abundat, ad cha- racteres autem, non ad affinitatem, pertinentibus. J2gardh, Classes Plantarum. PLANORBIS BICARINATUS, Say. PLATE 1. FIGS. 1 6. P. testa utrinque ad peripheriam angulata: superne late umbilicata, subtus valde depressa: anfractibus tribus fusco- lutescente. SYNONYMS AND REFERENCES. P. BICARINATUS, SAY. Nich. Encyc. (Amer. ed.) art. Conchology, No. 2, pi. i. fig. 4. American Conchology, pi. 54, fig. 3. HELIX ANGULATUS, RACKETT. Lin. Tr., xiv. pi. 5. fig. 1. " " WOOD'S Cat. supl., pi. 7. fig. 12. P. BICARINATUS, SowERBy's Genera, fig. 4. P. ENGONATUSJ CON. New fr. w. shells, pi. 9, fig. 8. P. BICARINATUS, GOULD. Invert, of Mass., p. 203, fig. 134. HELISOMA BICARINATA, SWAINSON. Malac., p. 337. DESCRIPTION. ANIMAL with variable tentacles, which are very long upon some individuals, and shorter upon others; sometimes they are of different length upon the same individual; the general color is yellowish-brown, spotted with whitish or yellowish dust-like dots, forming short lines along the sides of the head, extending back- PLANORBIS BICARINATUS. 7 wards from the posterior base of the tentacles; there is a similarly dotted spot upon each side of the head between the tentacles and in front of the eyes; the mouth is reddish. SHELL with rather more than three complete whirls, which are angulated upon each side near the periphery; the carina) do riot extend to the edge of the aperture in old shells; the spire is upon the left side, and is depressed about as deeply as the umbilicated side; the right margin of the labrum is upon the general plane of that side of the shell, whilst the left margin extends beyond the plane of the penul- timate whirl; the carina upon the left side forms a smaller spiral than that on the opposite side. COLOR of the outside brownish; of the inside chesnut, with pale lines in the grooves formed by the carinse. VARIETY unicarinatus. Shell small, with the whirls of the right side rounded; the carina (on the left side) revolves closely, so as to form a very narrow umbilic, and the aperture is much extended towards the left. Inhabits the Schuyl- kill. VARIETY angistoma. Shell small, aperture campanulate, with the throat narrowed. 8 PLANORBIS BICARINATUS. MONSTROSITY. P. engonatus, Conrad; of which I have seen but the single original spe- cimen in Mr. Mason's collection. GEOGRAPHICAL DISTRIBUTION. General from New England to Georgia; and from the North- west Territory to Tennessee, extremes included. Dr. Richardson found it from Lake Superior to Saskatchewan. OBSERVATIONS. This very common species inhabits quiet waters, along the surface of which it may be frequently seen moving in an inverted position. Its food is mud, impregnated with vegetable matter. The foot is sometimes reddish, and swollen by a blood-like liquid, which is dis- charged if the animal be disturbed. The ova are deposited from March to July, in small, yellow, irregular, and rather solid masses. It appears to be easily affected by cold, as it sinks into the mud, when the temperature decreases slightly, and penetrates deeply to hybernate; having the pulmonary cavity filled with air. The form of the anterior portion of the head, is well adapted to enable the animal to force its way through a soft material. PLANORBIS CAMPANULATUS, Say. PLATE 1. FIGS. 7 11. P. testa ochracea, sinistrorsum subplana, dextrorsum profunde umbilicata: anfractibus 4, transversim striatis: apertura campanulata, intus angustata. SYNONYMS AND REFERENCES. P. CAMPANULATUS, SAY. Jour. Acad. Nat. Sci., vol. 2, p. 166. P. CAMPANULATUS) GOULD. Invert, of Mass., p. 204, fig. 133. DESCRIPTION. SHELL compact, composed of four slowly en- larging, flattened whirls, striated by the lines of growth: right or upper side deeply umbilicated, the last turn plane, or slightly concave: the left, or spire side, is plane, or but slightly depressed: sutures distinctly marked: aperture deflected to the left, much dilated, the throat narrowed by a thick deposit on its anterior surface; peritreme very oblique; labium meeting two-thirds of the diameter of the penultimate whirl. COLOR yellowish or fuscous, inside bluish, yellowish, or chesnut. K 2 10 PLANORBIS CAMPANULATUS. GEOGRAPHICAL DISTRIBUTION. Inhabits New England, New York, Ohio, Illinois, and the Northwest Territory. OBSERVATIONS. Remarkable for the deflection and dilatation of the extremity of the last whirl, the narrow- ness of the aperture within; and in having the later growths of the spiral but little larger, and sometimes smaller, than in the preceding por- tions. EXPLANATION OF PLATE 1. Figure 2 represents the animal in its normal position, the shell being thrown to the left, and the tip of the apex consequently downwards; and 1, the right, upper, obverse, or umbilicated side; 4 is a view of the aperture, presenting the penultimate whirl of a greater diameter than sometimes occurs; 5 and 6 the distorted variety engonatus; 1 and 3 are taken from large shells, but I have found a single in- dividual with a diameter of three-fourths of an inch. Figures 7 and 11 represent P. campanulatus, 8 and 10 being im- mature. 11 PLANORBIS GLABRATUS, Say. PLATE 2. FIGS. 13. P. testa glabr&, vel subrugosa; anfractibus 5 ecarinatis et cylindraceis: apertura obliqua. SYNONYMS AND REFERENCES. P. GLABRATUS, SAY. Journ. Acad. Nat. Sci., vol. 1. p. 280, June 1818. Nich. Encyc., 3d Am. ed., art. Conch. Planorbis, No. 4. DESCRIPTION. SHELL "sinistral;* whirls about five, glabrous or obsoletely rugose, polished, destitute of any appearance of carina: spire perfectly regular, a little concave: umbilicus large, regularly and deeply concave, exhibiting all the volutions to the summit: aperture declining, remarkably oblique with respect to the transverse diameter. Breadth nearly nine-tenths of an inch." Say. COLOR corneous, or light brown. GEOGRAPHICAL DISTRIBUTION. Say's shells were from South Carolina: figs. 1 and 3 were drawn * Say would have considered the shell of P. corneus sinistral. 12 PLANORBIS GLABRATUS. from Mexican ? shells, and fig. 2 from a New Orleans specimen. Mr. Nuttall has placed an individual in the Academy's collection, which he found in Oregon. OBSERVATIONS. My shells do not agree perfectly with Say's description, copied above; yet they most proba- bly constitute the species he had in view. They differ from P. trivolvis by having a much more oblique peritreme, the whirls more nearly cylin- drical, the diameter increasing less rapidly, and without any tendency to carination upon the left side. 13 PLANORBIS TRIVOLVIS, Say. \ PLATE 2. FIGS. 47. P. testa utrinque excavata, ad sinistram subcarinata, anfractibus 4 subcylindraceis: pagina dextra in medio umbilicata. SYNONYMS AND REFERENCES. LISTER. Conch, tab. 140, fig. 46. P. TRIVOLVIS, SAY. Nich Encyc., art. Conchology, pi. 2, fig. 2. Am. Conchology, pi. 54, fig. 2. Bulla fluviatilis, (non Turt.,) Journ. Acad., ii. p. 31. (Junior.) P. CORPULENTUS, SAY. WniTTEMORE. Am. Journ. Sci., vol. 38, p. 193, P. REGULARI^ LEA. Proc. Am. P. S., vol. 2, p. 32. DESCRIPTION. ANIMAL "dark russet or dusky, covered with pale yellowish dots." Gould. SHELL flattened laterally, having four sub- cylindrical whirls, which are finely striated across by the lines of growth: left side slightly carinated, the carina being most apparent upon the inner whirls: spire slightly impressed, and (within the last whirl) nearly level: there are two and a half whirls visible upon the right 14 PLANORBIS TRJVOLVIS. side, the antepenultimate disappearing within the umbilical cavity: aperture large, vaulted anteriorly and slightly thickened within the margin; its faces project considerably beyond the planes of the shell. COLOR rufous, or yellowish-brown. GEOGRAPHICAL DISTRIBUTION. Occurs in New England, New York, Lake Erie, the Delaware and Schuylkill, and in the Northwest Territory. Dr. Richardson found it from Lake Superior to Saskatchewan. OBSERVATIONS. The peritreme is not as oblique as in P. glabratus, and both sides of the aperture pro- ject beyond the penultimate whirl, except in the variety fallax, pi. 3, fig. 1; whence it happens in the latter, that the sides of the shell are nearly parallel, from the slight increase of the transverse diameter of the whirls. Bulla fluviatilis, Say, and Planorbis regularis, Lea, are the young of this species, first named by the former, and more recently revived by the latter. If it were a distinct species, the original name should be preserved, as it is not more objectionable thanfontinalis, lacustris, or fluviatilis, applied to Physa and Ancylus; or fluviatilis, instead of its proper name, to an Anodon. 15 P. TRIVOLVIS, VAR. FALLAX. PLATE 3. FIGS. I 3. P. testa subdiaphana; pagina sinistra carinata, calicifor- mi; calice lato, minime profundo: anfractibus 4, minute striatis: suturis impressis. SYNONYMS AND REFERENCES. P. LENTUS, SAY, GOULD. Invert, of Mass., p. 202, fig. 132. DESCRIPTION. ANIMAL dark brown, minutely dotted with ochre-yellow, upon the parts which are usually exposed: tentacles very long, colored like the body, except that the tint is somewhat lighter near the base: foot, posterior to the neck, about equal in length to the head in front of the ten- tacles. SHELL thin in texture, translucent, and trans- versely striate: two and a half turns are visible above, the remaining ones disappearing in the narrow umbilic: lower side carinated, having a wide, shallow cup, as in figure 9, when the left posterior angle of the aperture advances along the carina; but the symmetry of the cup dis- 16 PLANORBIS TRIVOLVIS. appears, when the inner portion of the last whirl revolves to the right of the carina, as in figure 3; in this case, the right margin of the aperture is nearly level with this side of the shell, but it is frequently thrown below, or to the left of it, when it bears some resemblance to figure 5: aperture slightly compressed ante- riorly, the left margin extending beyond the plane of the shell. COLOR light brown, sometimes greenish. MONSTROSITY. Posterior extremity of the foot divided. GEOGRAPHICAL DISTRIBUTION. Massachusetts, Lake Erie, Indiana. ? OBSERVATIONS. In color and consistency, the ova resemble those of P. bicarinatus. Dr. Gould has ex- pressed an opinion, that if this be not P. lentus, it must be an uncharacterized species. He re- marks that it is "a darker shell than P. trivolvis, and is distinguished from it by its left side and its aperture. The cup of the left side is less smooth and regular, and is not bounded by the sharp, elevated line; when this shell is laid upon its right or upper side, the lip of that side will PLANORBIS TRIVOLVIS. 17 scarcely touch the plane on which it lies; while, in P. trivolvis, the shell would be lifted by the lip; the aperture has not the sharp angle of the left side, produced by the termination of the carina, but in the young stages it is difficult to distinguish the two." Professor Adams remarks that "P. lentus, P. corpulentus, and P. trivolvis, of Say, are un- doubtedly varieties of one species;"* but he sent me large specimens of P. trivolvis, (pi. 2, fig. 6,) as P. corpulentus; and believed the shell now under consideration to belong to P. lentus. I have figured it upon the same plate with the latter, to afford a ready comparison between them; and have thought best to describe it at large, under a distinct heading. I have seen it living in the vicinity of Boston, but have ex- amined so small a number of individuals, that I do not feel myself competent to make a final decision between two authors whose location gives them facilities which I do not enjoy. * Hist, of Vermont, Appendix. K 3 18 PLANORBIS LENTUS, Say. PLATE 3. FIGS. 46. P. testa opaca, utrinque angulata; superne profimde um- bilicata; subtus anguste excavata: anfractibus 4 5 crassis, ultimo sinistrorsum extendens: apertura longula. SYNONYMS AND REFERENCES. P. LENTUS, SAY. Am. Conchology, pi. 54, fig. 1. DESCRIPTION. SHELL dense, wide, and compact, composed of four or five coarsely striated, convex whirls, of which the last one, as it approaches its ter- mination, deflects to the left, so that the right portion of the labium leaves about one-third of the penultimate whirl to the right of it, the aperture or labium meeting the remaining two- thirds: aperture extended in front, and in con- sequence of the lower carina, having an angle near its junction with the labium: sutures dis- tinct: cup of the left side narrow, and rather deep. COLOR yellowish-brown. GEOGRAPHICAL DISTRIBUTION. Found in the PLANORBIS CORPULENTUS. 19 vicinity of New Orleans: "South Carolina." Dr. R. E. Griffith. OBSERVATIONS. Distinguished from P. trivolvis, var. fallax, by its greater size and density, the stronger de- velopment of the upper carina, and of the lines of accretion; the more open umbilic above, and narrower and deeper excavation of the left side; the shape of the aperture, the curvature of the striae; and finally, by the greater constancy and extent of the deflexion of the last turn, to the left of the obverse plane of the shell. PLANORBIS CORPULENTUS, Say. PLATE 3. FIGS. 79. P. testa, magna, transverse latissima, supra late umbili- cata, subtus excavata: anfractibus 4 5 biangulatis, sese obtegentibus, rapide accrescentibus; rugis exaratis. SYNONYMS AND REFERENCES. P. CORPULENTUS, SAY. Long's Expedition to the source of St. Peter's river, p. 362, pi. 15, fig. 9. 20 PLANORBIS CORPULENTUS. DESCRIPTION. SHELL large, composed of four or five strap- shaped, compact whirls, having a considerable transverse diameter (from carina to carina) which much exceeds the diameter of the aper- ture, taken at right angles to the axis: the lines of growth are distant, elevated, and conspicu- ous, giving the surface a rough appearance: the right side is widely and deeply umbilicated, and has a strong tendency to obtuse carination; the left side is carinated, and presents a wide, and rather deep cup: the aperture has but little obliquity, extends considerably to the right and left beyond the penultimate whirl, and has the labium expanded. COLOR light ochraceous, the aperture some- times presenting a zone of chesnut. GEOGRAPHICAL DISTRIBUTION. Common in Winnipeek river and lake, Lake of the Woods, and Rainy lake. Say. Lewis' river. Mr. Nuttall, (specimen figured.) OBSERVATIONS. The distinguishing character of this species, is the width and flatness of the whirls, in a PLANORBIS EXACUTUS. 21 direction parallel with the axis; but from the rarity of the shell in collections, overgrown spe- cimens of P. trivolvis, (pi. 2, fig. 5,) have been supposed to represent it; and it has accordingly been referred to this species, or described as resembling it very closely. PLANORBIS EXACUTUS, Say. PLATE 4. FIGS. 1 3. P. testa lenticular!, parva, tenui, umbilicata; ad periphae- riam carinata: anfractibus 4, supra planis, infra convexis: apertura obliqua. SYNONYMS AND REFERENCES. P. EXACUOUS, SAY. Journ. Acad. Nat. Sci., vol. 2, p. 166. P. EXACUTUS, GOULD. Invert, of Mass., p. 208, fig. 137. LEA. Tr. Am. Phil. Soc. 2d, P. LENS AND BRONGNIART, PALUDINA HYALINA, s., vol. 6. p. 68, pi. 32, fig. 83. Proceedings, vol. 2. p. 242. DESCRIPTION. ANIMAL reddish-brown, tentacles short and slender, eyes black, foot short. 22 PLANORBIS EXACUTUS. SHELL lenticular, fragile, translucent, and fine- ly striate; slightly convex, but concave towards the centre, and margined with a carina above: 7 O convex, and widely umbilicated below: sutures moderately deep: aperture very oblique, angu- lated by the carina in front, and having the middle of the right margin strongly arched. COLOR light corneous. GEOGRAPHICAL DISTRIBUTION. Inhabits New England, New York, and the western states. FOREIGN ANALOGUE. P. nitidus, Gray's Tur- ton, fig. 93. OBSERVATIONS. "It appears to be pretty closely allied to P. nitidus of Europe, but it is larger, the umbilicus much more dilated, and the aperture does not embrace the penultimate whirl so profoundly." Say. Dr. Gould remarks that it differs from the European analogue in having the aperture "entirely below the sharp edge, instead of em- bracing nearly an equal portion on each side, as in that shell." Not having European speci- mens, I have not been able to institute a. com- parison with ours. It is distinguished from P. deflectus by the flatness of the whirls, and less PLANORBIS DILATATUS. 23 impressed suture, upon the right side; and from P. dilatalus, by greater magnitude, wider um- bilic, and oblique aperture. Dr. Gould thinks it probable that P. lens is identical with the next species; but the figure and description of it appear to agree more nearly with P. exacutus; and this opinion is strengthened by the fact that Mr. Lea proposed brongniartiana (instead of lens which was pre-occupied) more than a year after the publication of Dr. Gould's spe- cies, and without making any allusion to the dilatatus of Pfeiffer. A less uncouth name than the unlatinized one of M. Brongniart might have been proposed; for as it now stands, it is unpronounceable as a latin word, and the femi- nine form is objectionable, although, in the present instance not as much so as the corresponding masculine term would be. PLANORBIS DILATATUS, Gould. PLATE 4. FIGS. 1618. P. testti minuta, margine carinato; infra anguste umbili- cata; supra subplana, sutura impressa: apertura subovata, et dilatata. SYNONYMS AND REFERENCES. P. DILATATUS, GOULD. Invert, of Mass., (1841,) p. 210, fig. 140. 24 PLANORBIS DILATATUS. DESCRIPTION. SHELL small, delicate, wide, carinated, with the lines of increment fine; closely umbilicated below; slightly convex above, with the suture conspicuous, and the apex slightly impressed: body whirl enlarging rapidly, and losing the well defined carina as it approaches the peri- treme, which, however, is still somewhat modi- fied by it. COLOR light brown, translucent. GEOGRAPHICAL DISTRIBUTION. Massachusetts, Ohio, ? Delaware river, Maryland. OBSERVATIONS. More closely rolled, and wider transversely than P. exacutus or P. parvus; and distinguished from both by the narrow umbilication of the left side. The right, or upper side, resembles that of P. exacutus, but the margin is more ob- tusely carinated, and the edge of the peritreme is not so convex. Herr Pfeiffer has described an European Planorbis dilatatus in Wiegmann's Archiv. fur Naturgeschichte, 1841, p. 225. If it be a true species, it will be rather difficult to determine PLANORBIS DEFLECTUS. 25 the question of priority; as the German peri- odical, and Dr. Gould's work, were published the same year. The later species might be called dilatus, with the citation of the author to whom it belongs as a species. PLANORBIS DEFLECTUS, Say. PLATE 4. FIGS. 4 7. P. testa discoidea, ad periphaeriam obtuse carinata, utrinque concav& et similiter excavata: labio in anfractum ultimum extenso: anfractibus 4 compressis. SYNONYMS AND REFERENCES. PLANORBIS DEFLECTUS, SAY. Long's Expedition to St. Peter's river, p. 261, pi. 15, fig. 8. PLANORBIS DEFLECTUS, GOULD. Invert, of Mass., 136. P. VIRENS, ADAMS. Bost. Journ. N. H., v. 3, pi. 3, fig. 16. DESCRIPTION. ANIMAL "dusky above, and with a still darker line to tip of tentacula." Gould. SHELL discoidal, thin in texture, smooth, and finely striate, with the margin obtusely cari- nated: sides exhibiting about one-half of the K 4 26 PLANORBIS DEFLECTUS. inner whirls, and, with the sutures, moderately and equally excavated: last fourth of the ulti- mate volution with a strong tendency to diverge toward the left, (figs. 4, 5,) frequently not in con- tact with the preceding whirl: aperture large, very oblique: peritreme circular, except where the labium advances upon the penult whirl. COLOR light corneous. GEOGRAPHICAL DISTRIBUTION. New England, Ohio, Northwest Territory. OBSERVATIONS. The peculiar deflection of the aperture, in most individuals of this species, and the want of a sharp carina, readily distinguishes it from P. exacutus. Unless the deflection be very great, as in figure 5, the lower side can scarcely be styled umbilicated, approaching P. parvus in this respect. The species of this genus which have the apex of the shell above, or on the right side, appear to be most liable to deviations or mon- strosities, and the whirls appear to vacillate in their revolution, as if a certain maintaining power were wanting, to impress, in a decided manner, the same characters upon all the indi- viduals of a species. 27 PLANORBIS PARVUS, Say. PLATE 4. FIGS. 1923. P. testa simplice, minimi, tenui, laevi, valde compressa; supra in medio impressa; infra late et minime excavata: anfractibus 4, rotundatis, utrinque pariter conspicuis: suturis impressis. SYNONYMS AND REFERENCES. P. PARVUS, SAY. Nich. Encyc., Am. ed., pi. 1, fig. 5. " " GOULD. Invert, of Mass., p. 209, fig. 139. P. ELEVATUS, ADAMS. Boston Journ. N. H., 3, pi. 3, fig. 15. " " GOULD. Invert, of Mass., p. 207. LISTER, tab. 139, figs. 4544? "FAVANNE, pi. 63, fig. 3. DILLWYN." Say, MS. DESCRIPTION. ANIMAL brown, foot extending from the labrum to the centre of the shell, rounded posteriorly, sides parallel. SHELL small, compressed, minutely striate, smooth, flat above, with the centre impressed: left side with a broad, shallow concavity: whirls four, a great part of them, with the apex, visible to the centre, on both sides: sutures equally 28 PLANORBIS PARVUS. deep: aperture oval, oblique, longer than wide, peritreme undeviating. COLOR of the shell, light wood-brown, some- times with a tinge of greenish. GEOGRAPHICAL DISTRIBUTION. Very generally diffused over the eastern, middle, and western states; and found in the Northwest Territory. FOREIGN ANALOGUE. P. laevis. Gray's Tur- ton, fig. 148. OBSERVATIONS. Except P. dilatatus, this is our smallest spe- cies; individuals of a fourth of an inch in size being of rare occurrence. Its smaller trans- verse diameter, and the more open concavity of the left side, distinguish it from small speci- mens of P. deflectus, to which it is allied by a tendency to deflect the last whirl towards the left, and of which figure 20 presents an extreme case. Individuals in which this character is pretty well developed, constitute P. elevatus, Adams. PLANORBIS ALBUS, Muller. PLATE 4. FIGS. 8 10. P. testa pallida, tenui, hirsuta, utrinque anguste in medio excavata: anfractibus 4 rotundatis, lineis revolventibus his- pidis. SYNONYMS AND REFERENCES. P. ALBUS, MULLER. Verm. ii. 164. P. HISPID us, DRAP., p. 43, pi. 1, figs. 45 48. " " LAMARCK. An. sans vert., vol. 8, p. 387. P. HIRSUTUS, GOULD. Invert, of Mass., p. 206, fig. 135. DESCRIPTION. ANIMAL dark reddish-brown, with a light line running back from the posterior base of the tentacles, central line of these, dark: eyes dis- tinct black points, at the antero-internal base of the tentacles. SHELL pale, fragile, composed of four inflated, compact, circular whirls, equally convex on both sides, marked by numerous hispid, revolving lines, which are covered with deciduous bristles: each side with a nearly similar, deep, and rather narrow excavation: aperture oblique, nearly cir- cular. 30 PLANORBIS ARMIGERUS. COLOR whitish, with a very pale tinge of brownish. GEOGRAPHICAL DISTRIBUTION. Inhabits Eu- rope, New England, "Lake Superior to Sas- katchewan." OBSERVATIONS. The shell is so closely rolled, that but little of the inner turns appear; and when perfect, is easily recognised by the hirsute exterior. Dr. Gould compares ours with the European shell, but in assuming it as distinct, says it is thinner, with the last whirl increasing more rapidly, and that "it maintains its yellowish-brown color, whereas P. albus assumes a spermaceti, or still whiter appearance. The lines too, disappear almost entirely, when the epidermis is gone." PLANORBIS ARMIGERUS, Say. PLATE 4. FIGS. 1115. P. testa brunnea, supra plana; subtus profunde umbili- cata: anfractibus 4 rotundatis; suturis impressis: apertura intus 6-dentata. PLANORBIS ARMIGERUS. 31 SYNONYMS AND REFERENCES. P. ARMIGERUS, SAY. Journ. Acad. Nat. Sc., vol. 2, p. 164. " " GOULD. Invert, of Mass., p. 205, fig. 138. DESCRIPTION. ANIMAL "very active, of a blue-black or slate color; foot long and narrow: respiratory groove very acutely pointed." Gould. SHELL polished, with four subcylindrical whirls, subcarinated upon the left side, and having the lines of accretion very fine: right side nearly plane, the centre slightly impressed: left side widely and deeply umbilicated, and exhibiting all the volutions: aperture subrotund, oblique, armed far within (a fig. 12) with six white teeth, which nearly close the aperture, the largest thin and oblique, running backwards from the left to the right side, (fig. 15,) on the left of this is a small one, and around the vault four others, gradually increasing in size from the left to the right side. COLOR light brown; peritreme and an occa- sional varix, much darker. GEOGRAPHICAL DISTRIBUTION. Eastern, mid- dle, and western states, and the Northwest Ter- ritory. 32 .PLANORBIS ARMIGERUS. OBSERVATIONS. The teeth within the aperture may be con- sidered analogous to those of certain Helices, but they differ in the important point of being present at every stage of growth. They are present when the shell is less than a line in length, and as but one set exists in full grown individuals, we must infer that they are absorbed and reproduced from time to time. In over- grown specimens, like those figured, it some- times happens that the teeth are wanting; as if, after their absorption, the energies of the ani- mal were too far exhausted to reproduce them. The outer ones seem to be formed successively from left to right; the small one on the right appearing last, and in its absence, the shell has been described by Say and Gould as being but five-dentate. In Segmentina, three large teeth project, so as to leave a triradiated aperture for the pass- age of the Mollusk; and as the earlier ones are not absorbed, several of the partitions thus formed, are always present. 1^6. P SICARIN-ATUS, Say. 7.._11. P CAMPANULATirS, Say. Mi36 Helen E LawBon del.ct col. )M l_3. P GLABRAT17S Say. 4__7. P TSIV'OlVTS. LLasreop delet col 1-3. P Var FALLAX. 4_6. F. LENTUS. 1-3. ^ KXACDTffS Say. 11-15. J AKMIGERUS Say. 4_7. / 16 ._18. J DILATATU-S Gould. 19_23. ,P PARTU~S Say. 9 I i t L A. liiri/LAXIS. 'o 5 A. CWSClfR(fS.^\ 4. ^. DIAPHANUS,- Raid. 8. ^. CRASS US,. .HaJd. GENUS A N C Y L U S, Mutter, Gray. PLATE 1. FIG. 1. Testa simplex pATELLJEformis; apex posterior, dextro- vertens: cicatrix submarginalis, sinistrorsum interrupta. SYNONYMS AND REFERENCES. PATELLA, LINNJEUS, and Linnaean authors. CREPIDULA, FLEMING. Encycl. rfNCYLUS, MiJLLER, LAMARCK, SoWERBY. " LAMARCK. Animaux sans vertebres. " SOWERBY. Genera of Shells. " GRAY. Turton's Manual, p. 247. DESCRIPTION. ANIMAL conical, not involute, covered by the concavity of the shell: head emarginate in front, with a small flap upon each side; tentacles short, compressed, widest at base, with the sides nearly parallel: foot united to the body through- out, except at the anterior extremity, where it is free: mantle simple. Attached to the shell by a small portion of the back of the mantle: L 1 2 ANCYLUS. capable of a little extension beyond the shell, and of turning nearly at right angles to it. SHELL patelliform, simple, sinistral, with the apex directed backwards, and towards the right: pallial impression submarginal, interrupted upon the left side. EXAMPLE. Ancylus rivularis, Say. HABITS. Attached to the sides and lower surface of stones; or upon and within dead bivalve shells; either in running or quiet water. The American species, as far as can be ascer- tained, appear not to require access to the atmosphere. PHYSAD^E, p. 11. OBSERVATIONS. In the genus Siphonaria the pallial impression is interrupted in front, and Patella has the apex directed forwards. The breathing aperture is upon the left side, next the labrum, or outer lip, as in Physa; which it also resembles in having the apex directed to the right. The tongue is long, slender, and covered with minute teeth, of which there are about eighty rows, and thirty teeth in each row, in A. rivularis; the only species I have examined. The edges of the mouth and head are covered with vibrillse. ANCYLUS. The allied genus Velletia, separated by Mr. Gray, is dextral; but as the pallial impression is obsolete in delicate shells, and the apex fre- quently so much eroded that its proper direction cannot be ascertained, it is sometimes extremely difficult to decide between the two genera. The species figured upon plate 1, appear to be true Ancyli, no native species of Velletia having yet come under my observation. Specific distinctions are but slightly marked in the Physadse; and in a genus like Ancylus, are particularly difficult to discover, from the great similarity of the spire and aperture; and the absence of the suture and columella, with the consequent variety of character which they present. Hence, the danger of multiplying spe- cies is greatly increased, especially in cases like the present, where several are characterized from a small number of individuals; and they must, consequently, be admitted with caution. The outline figures (marked a) upon the plate, represent the natural size of the shell in profile; and the dimensions are given as affording addi- tional means of identification. This has not been deemed necessary with those genera which are figured the natural size. ANCYLUS RIVULARIS, Say. PLATE 1. FIG. 1. A. testa ovata, sublata, subelevata, apice obtuso. SYNONYMS AND REFERENCES. A. RIVULARIS, SAY. Journ. Acad. Nat. Sci., I. 125. DESCRIPTION. ANIMAL plumbeois, minutely dotted with whitish: a central yellowish longitudinal line upon the head: foot emarginate in front, extend- ing to the mouth, where it is very thin. SHELL delicate, moderately elevated; sides slightly convex, diverging anteriorly: posterior and dextral slopes concave, anterior slope con- vex, and sinistral one nearly rectilinear: apex subacute, projecting, one-third of the shell posterior to it. COLOR light brown; nacre, in large individuals, white. DIMENSIONS. Long. 5, lat. 3.5, elev. 2 milli- metres. GEOGRAPHICAL DISTRIBUTION. The Delaware and Susquehanna. ANCYLUS RIVULARIS. O VARIETY. A. BRUNNEUS. Flatter, narrower behind, posterior slope less concave. HAB. James river, Virginia, at Buchanan. OBSERVATIONS. Larger, and rather more elongate than A. tardus and depressus, and having the apex rather more posterior. Dr. Gould's figure 153 agrees very nearly with this species, but his description (p. 224) appears to belong to A. parallelus, as the elongate A. fluviatilis of Europe is noted as an allied species. ANCYLUS DEPRESSUS, Hold. PLATE 1. FIG. 2. A. parva, elliptica, pallida, tenui, diaphana, depressa; apice obtuso. DESCRIPTION. SHELL small, oval, elliptic, pale, thin in texture, depressed, ends similarly curved, sides convex, slope nearly rectilinear: apex obtuse, with more than one-third the shell behind it. DIMENSIONS. Long. 4, lat. 2.5, elev. 1.5 mil- limetres. GEOGRAPHICAL DISTRIBUTION. Holston river, in Washington county, southwestern Virginia. OBSERVATIONS. Paler, more depressed, and with a less promi- nent apex than A. rivularis and tardus; posterior slope less concave, than in the former; and not direct, as in the latter. ANCYLUS TARDUS, Say. PLATE 1. FIG. 3. A. testa parva, regular!, elliptica; elevata, apice obtuso. SYNONYMS AND REFERENCES. w5. TARDUS, SAY. Disseminator, Jan. 15th, 1830. Mrs. Say's reprint, p. 26. ADAMS. Thompson's History of Vermont. DESCRIPTION. SHELL pale and delicate, elliptical; apex ob- tuse, elevated; posterior and lateral slopes sub- rectilinear, anterior slope convex. DIMENSIONS. Long. 0.25, lat. 0.16, elev. 0.13 inch. Adams. GEOGRAPHICAL DISTRIBUTION. Found in the Wabash, and in Vermont. OBSERVATIONS. Higher, shorter, and more darkly coloured than A. depressus, and has the apex more nearly central. It is proportionally broader than A. rivularis, and not perceptibly widened before. 8 ANCYLUS DIAPHANUS, Hald. PLATE 1. FIG. 4. A. testa pallida, lata, tenui, subrotunda; apice submediali, obtuso. DESCRIPTION. SHELL thin in texture, diaphanous, very wide, nearly circular, depressed: apex obtuse, almost central: slope scarcely convex. COLOR very pale olivaceous, translucent, aper- ture white. DIMENSIONS. Long. 5.5, lat. 4.5, elev. 2 millim. GEOGRAPHICAL DISTRIBUTION. Discovered in Ohio, by Mr. Anthony. OBSERVATIONS. Distinguished by its circular and flattened form; and central, inconspicuous apex. ANCYLUS OBSCURUS, Hold. PLATE 1. FIG. 5. A. testa brunnea, ovata, latiuscula, subelevata. DESCRIPTION. SHELL ovate, somewhat elevated, rather wide, apex but slightly projecting, rather more than one-third of the shell posterior: lateral margins slightly convex: lateral slopes rectilinear; pos- terior slope with a very slight depression; ante- rior slope nearly rectilinear. COLOR dark brown, margin diaphanous. DIMENSIONS. Long. 5, lat. 3.5, elev. 1.5 mill. GEOGRAPHICAL DISTRIBUTION. Founcf in No- lachucky river, below Greenville. OBSERVATIONS. Rather wider than A. rivularis and depressus; more depressed than the former, and lighter colored than the latter. A single specimen was obtained, of which the margin is defective. L 2 10 ANCYLUS FILOSUS, Conrad. A. testa ovali, elevata; lineis elevatis radiatis prominen- tibus. SYNONYMS AND REFERENCES. ANCYLUS FILOSUS, CONRAD. New Freshwater Shells, p. 57. DESCRIPTION. SHELL "regularly oval, rather elevated; with numerous radiating prominent lines; apex very prominent, inclined, eroded, not nearly central." OBSERVATIONS. Found by Mr. Conrad in Blackwarrior river, south of Blount's springs, Alabama, attached to species of Melania. It is readily distinguished by the elevated radiating lines. Not having a specimen, I give it only a provisional place in this genus. 11 ANCYLUS PARALLELUS, Hald. PLATE 1. FIG. 6. A. testa elongate, angusta, depressa, diaphana, apice subacuto. SYNONYMS AND REFERENCES. A. PARALLELUS. This work; January, 1841. " ADAMS. Hist, of Vermont. A. RIVULARIS, GOULD. Invert, of Mass., p. 224. DESCRIPTION. SHELL pale, thin, and delicate; lengthened, sides subrectilinear, diverging slightly forwards: apex rather sharp, conspicuous, with two-fifths of the shell posterior to it. DIMENSIONS. Long. 0.25, lat. 0.15, elev. 0.08 inch. Adams. GEOGRAPHICAL DISTRIBUTION. Inhabits New England. OBSERVATIONS. In general appearance, resembles Velletia lacustris, Miill., of Europe, but is at once distinguishable by having the apex directed 12 ANCYLUS FUSCUS. towards the right. Professor Adams remarks "It was supposed to be Say's A. rivularis, not on account of any resemblance between the two shells, but from the meagreness of the description. From some remarks of this learned naturalist, comparing A. rivularis with A. tardus, it seems probable that the former is not an elongate species." Appendix to Thompson's History of Vermont. ANCYLUS FUSCUS, Adams. PLATE 1. FIG. 7. A. testa ovata, depressa; apice obtuso; epidermide fusca, ultra quam peritremam producitur. SYNONYMS AND REFERENCES. A. FUSCUS, ADAMS. Boston Journ. Nat. Hist., vol. iii. p. 329, pi. 3, fig. 17. A. FUSCUS, GOULD. Invert, of Mass., p. 224, fig. 152. DESCRIPTION. SHELL thin in texture, ovate, depressed, a ANCYLUS FUSCUS. 13 little narrowed posteriorly; lateral margins slightly convex: anterior, posterior, and lateral slopes, rectilinear: apex very obtuse, subcentral: epidermis extending beyond the peritreme. COLOR translucent pale yellow, epidermis fuscous, frequently discolored so as to appear dark brown. DIMENSIONS. Long. 7.5, lat. 5, elev. 2 mill. GEOGRAPHICAL DISTRIBUTION. Inhabits Fresh Pond, near Harvard, Massachusetts. OBSERVATIONS. This large species is remarkable for the manner in which the periostraca extends beyond the margin of the shell, upon the object to which the mollusk is attached; so as to give to the limb the aspect of being reflexed. 14 ANCYLUS CRASSUS, Raid. PLATE 1. FIG. 8. A. testa magna, lala, ovata, solidula, elevata. DESCRIPTION. SHELL coarse, somewhat ponderous, wide, ovate, elevated; lines of growth conspicuous; apex eroded, placed far back: anterior and lateral slopes convex, posterior slope steep and rectilinear. COLOR opake chesnut-brown. DIMENSIONS. Long. 8, lat. 6.25, elev. 3 mill. GEOGRAPHICAL DISTRIBUTION. Brought from Oregon by Mr. Nuttall. OBSERVATIONS. Distinguished by its opacity, and thick texture, all the preceding species being more or less translucent and delicate. INDEX. Synonyms, and the names of such proposed species as have not yet been recognised from the characters indicated, are printed in italics. Acella, p. 14. . . LIMNEA, p. 6 Amphipeplea, . : "3, 14 Ancylus crassus, ... 14 depressus, ... 6 diaphanus, ... 8 filosus, .... 10 fuscus 12 obscurus, .... 9 parallelus, ... 11 rivularis, .... 4 tardus, .... 7 Aplexa, 14,37 Buccinum,) . . . LIMNEA, 1 Bulimnea, . . . . " 6 Bulimus, .... PHYSA, 23 Bulinus, " 23 Bulla crassula, Dillw. " 23 fontinalis, Chemn. " 23, 29 Jluviatilis, PLANORBIS, 13 hypnorum, . PHYSA, 36 Crepidula, . . ANCYLUS, 1 Diastropha, 14 Helix, LIMNEA, 1 angulatus, PLANORBIS, 6 Leptolimnea, . . . LIMNEA, 1 Limnea, .... PHYSA, 1 Limnea acuminata, ... 38 apicina, .... 37 appressa, .... 18 attenuata, ... 28 bulimoides, ... 44 caperata, .... 34 catascopium, . 6, 52 Limnea casta, Proc. Am. P. S.ii. ..... 33 coarctata, .... 39 colurnella, ... 38 chalybea, .... " curta, Proc. Am. P. S.ii 33 decollata, .... 52 desidiosa, .... 31 desidiosa, .... 48 dutortus, .... 26 elodes, 20 emarginata, ... 10 exigua, Proc. Am. P. S. ii.' exilis, . . expansa, . ferruginea, fragilis, 33 26 29 49 20,23 fusiformis, Proc. Am. P. S.ii 33 galbana, .... 51 gracilis, .... 50 grijjithiana, Proc. Am. P. S. ii 33 heterostropha, PHYSA, 23 humilis, jugularis, . . . . kirtlandiana, Proc. Am. P. S. ii. . . macro stoma. , 41 16 33 38 13 41 INDEX. Limnea navicula, .... 38 nuttalliana, Proc. Am. P.S.ii 33 pallida, .... 45 palustris, .... 20 parva, 41 philadelphica, . . 31 pinguis, .... 6 planulata, Proc. Am. P.S.ii 33 plica, Proc. Am. P. S.ii 33 reflexa, .... 26 rubella, Proc. Am. P. S.ii 33 rugosa, .... 15 rustica, Proc. Am. P. S. ii 33 sericatus, Ziegl. . 6 serrata, .... 12 solida, 37 speciosus, .... 18 stagnalis, .... 16 slrigosa, Proc. Am. P.S.ii 33 succiniformis, . . 40 umbilicatcb) ... 34 umbrosa, . . 24, 55? Paludina hyalina, PLANORBIS, 21 Physa ancillaria, .... 27 aurea, 23 concolor, 30 distorta, 35 elliptica, 32 elongata, 36 fontana, 26 fontinaliSj .... " fragilis, 31 globosa, ..... 38 gyrina, 32 heterostropha, . . 23 hildrethiana, Proc. Am. P.S.ii 32 hypnorum, .... 36 injlata, Proc. Am. P. S.ii 32 Physa integra, 33 microstoma, ... 39 osculans, .... 29 pomilia, Con. Am. J. Sci.xxv. . . . 343 sayi, 27 scalaris, ..... 34 trustensis, Proc. Am. P.S.ii 32 Physella, . 14 Physodon, " Planorbella, " Planorbina, " Planorbis albus, .... 29 antrosus, Con. Am. J. Sc. xxv. . . 343 armigerus, ... 30 bellus, Proc. Am. P.S.ii. ... 32 bicarinatus, . . 6 buchanensis, Proc. Am. P. S. ii. . 32 campanulatus, . 9 corpulentus, . . 19 corpulentus, ... 13 deflectus, ... 25 dilatatus, ... 23 elexatus y .... 27 engonatus, ... 6 exacutus, ... 21 fallax, .... 15 glabratus, ... 11 hirsutus, .... 29 hispidus . . . . " lens, 21 lentus, .... 18 lentus, .... 15 parallelus, Say, . * parvus, .... 27 regularis, ... 13 Irivolvis, . . . u virens, .... 25 Planorbula, 14 Radix, " Segmentina, 14 Stagnicolaj . . . LIMNEA, 1 * Jour. Acad. Nat. Sci., ii. p. 164. Probably Helix lineata. MONOGEAPH OF THE FRESHWATER UNIVALVE MOLLUSCA OF THE UNITED STATES, INCLUDING NOTICES OF SPECIES IN OTHER PARTS OF NORTH AMERICA. BY S. S. HALDEMAN. TURBID^. Die Erfodernisse einer guten Abbildung sind ; hochste Treue in Dars- tellung der Gestalt und Verhaltnisse, im Ausdrukke der Oberflache. . . Beobachtung der naturlichen Gr(5sse. . . Getreue Nachahmung der Farben. llliger, Terminologie, 1800, 101. PHILADELPHIA: 1845 TURBID^. Gasteropodous dioicous operculate testaceous aquatic mollusca, having a single pair of ten- tacles, with the eyes situated externally upon an enlargement of the base: shell spiral, more or less globose or subdiscoidal, with the aper- ture entire. The great and somewhat heterogeneous family Turbida^ nearly corresponds to the genus Turbo, Lin.; to Blainville's second family Cri- costomata, of his second order Asiphonobran- chiata; and to Cuvier's family of Trochoides (which includes the Melaniana) of his sixth order Pectinibranchiata. It includes, according to each of these systems, genera which, like Helicina, appear to belong more properly to the pneumonobranchiate section. Mr. J. E. Gray makes the genera Ampullaria, Paludina, and Valvata, the types of as many* distinct families. These genera are indeed very distinct, but whether they should be considered E 1 2 TURBID^:. as the representatives of families or subfamilies, is still an open question. I have here adopted the more enlarged signification of the term family, although I might for convenience have placed the few genera here described in La- marck's family Peristomata, to which they cor- respond. Mr. Swainson proposes the name Turbidse for a family at the head of which he places Amphibola, Schum., (Ampullacera, Quoy^ as a doubtful subfamily, after leaving the Physadae, to which the mollusk is allied in several im- portant particulars.'* The subfamily Ampul- larinae follows, including Valvata, Ampullaria and Paludina; and the subfamilies Melanianse and Turbinae are placed next, closing the family, which is thus made to stand between the Heli- cidae and Naticadae. The last arrangement has much to recom- mend it, the principle objection to it being the situation of the Helicidse before the more highly organized genera Ampullaria, Melania, &c. But this objection holds against every system * See Deshayes' Lamarck, viii. 538. TURBIDJE. 3 which is founded, as most are, upon a partial view of the organization. Thus the lowest members of the order Pisces, as the genera Amphioxus and Gastrobranchus, although they belong to one of the vertebrate classes, are lower in the scale of being than the insecta, which, in their turn, have been improperly placed below the akephalous mollusca, because the latter have a heart, an organ which could not be readily demonstrated in the former. Belonging to a family or division the greater part of the members of which are marine, I will not attempt to take a general view of the whole, contenting myself with giving the history of each of the four fluviatile genera found in the United States, under its proper head. In the arrangement of genera, as far as this work is concerned, (it having been necessary to determine the binder's signatures from the first,) it was deemed best to place the Melaniadae at the head, and enter the present family by Anculosa and Amnicola, which are nearly allied; leaving the Physadae by Ancylus to pass to the Limacidse. GENUS AMNICOLA, Gould, Hold. PLATE 1. FIG. 1. Testa parva vel minuta, PALUDINJE similis; operculum corneum, subspirale. SYNONYMS AND REFERENCES. PALUDINA, LAM. SAY, &c. HYDR OBI A ? H ARTM ANN. GOULD. Invert, of Massachusetts, p. 228. DESCRIPTION. AMIMAL with the head proboscidiform, rostrum subbifid at the extremity, and extending beyond the foot; mouth a longitudinal slit upon the inferior surface: tentacles setaceous, of equal length: eyes at the posterior external base, not pedunculate: foot subovate or lengthened, trun- cate anteriorly, the angles capable of being turned outwards as in VALVATA, but not to so great an extent; and it is incapable of the ex- tension beyond the rostrum observable in PALU- DINA. AMNICOLA. O SHELL short or lengthened conic, thin in tex- ture, composed of from 4 to 7 convex whirls, separated by a distinct suture: aperture oblique, peritreme simple, detached, or but slightly con- nected with the body whirl, and usually by a very small portion of its circumference poste- riorly; base usually perforate: operculum thin, corneous, composed of a few spiral volutions. HABITS. A. decisa and lustrica, where I have observed them, live upon the inferior surface of stones in running water. They are tolerably active, and retract suddenly when a shadow is passed over them. The ova are deposited in the month of March, in small oblong detached glairy masses, each of which contains appa- rently but one germ, which is situated at the larger end of the mass. The color of the germ is orange, of the mass yellowish transpa- rent, with a dark central line upon the surface from end to end. The progression, at least of the short species, is performed upon the foot alone, with a uniform gliding motion as in Physa. OBSERVATIONS. This natural genus seems at first view to be O AMNICOLA. allied to the terrestrial ? genus Nematura, Ben- son;* and, as far as the shell is concerned, it has also some affinity with Fleming's sestuary genus Cingula. It will probably be found to be identical with Hydrobia, Hartmann, if the Palu- dina thermalis be a proper example of it.t If the characters of Paludina parvula, Guilding, Zoological Journal iii. 537, pi. supp. 28, figs. 1 and 2,J are constant, it is possibly distinct from Amnicola; the foot being lengthened triangular, and the left tentacle twice the length of right one. It is difficult to separate the bare shells having a circular aperture, from Valvata and Cyclos- toma, and it is possible that porata may belong to the former, and one or two of the others to the latter genus. * Vide Sowerby's paper in Charlesworth's Mag. Nat. Hist. i. 217. f This European species is distinct from all those de- scribed herein. Among some notes made in 1840, but not since verified, I find that the foot and antennae are furnish- ed with vibrillae, which are interspersed with erect hairs upon the latter organs, the length of the vibrillae being about 0.01 millemeter; the hairs a little more. About 8 rows of pectinated branchiae were observed. ^ Copied in Swainson's Malacology (Cab. Cyc.) p. 198. AMNICOLA DECISA, Hald. PLATE 1. FIGS. 2, 3. A. testa virescente, imperforata; anfractibus 5 planius- culis; labio subrectilineari, in anfractum ultimum com- presso. Long. 4 mm. DESCRIPTION. ANIMAL dark colored; head blackish, getting lighter posteriorly; tentacles translucent, dark on the edges; an orange yellow spot at the posterior internal base of the tentacles: foot yellowish, thickly dotted with black above an- teriorly; anterior edge nearly as dark as the head; base of the foot thickly dotted with orange on each of the middle, the dotting being more sparse posteriorly, and entirely wanting anteriorly. SHELL rather short, conical; surface smooth, shining (when the dark foreign matter is re- moved) lines of growth fine; whirls 5, not very convex, suture imprest, base slightly perforate; aperture dilated semicircular, labium slightly 8 AMNICOLA DECISA. concave, in contact with the shell posteriorly, and nearly so throughout its length. COLOR pale green, and slightly translucent when the black foreign matter is removed. GEOGRAPHICAL DISTRIBUTION. Inhabits small streams connected with the Susquehanna, and has been observed in the Schuylkill by Dr. Griffith. ' OBSERVATIONS. Allied to Paludina similis, Mich., of Europe. A greater portion of the labium lies close to the shell in this species than in any other here described, except A. nicliniana, and A. tenuipes, which are slender species. At first view it might be taken for a minute Paludina decisa, and I have named it accordingly. In my cor- respondence I have hitherto called this species limosa. AMNICOLA CINCINNATIENSIS, Ant. PLATE 1. FIG. 4. A testst albida, laevi, umbilicata; aperturJt ovata, labio postice in anfractum ultimum attingente. Long. 6 mm. SYNONYMS AND REFERENCES. PALUDINA CINCINNATIENSIS, ANTHONY. Boston Journal of Natural History, vol. iii. p. 279, pi. 3, fig. 3. DESCRIPTION. SHELL "somewhat ventricose, subumbilicate, color delicate green: whorls four, smooth; spire entire at the apex and prominent; suture deeply impressed; aperture much dilated, approaching to orbicular, nearly half the length of the shell; length one-fifth of an inch." GEOGRAPHICAL DISTRIBUTION. Inhabits "the canal near Cincinnati clinging to small stones." This is the most robust species hitherto noticed amongst us; and is, in form, a miniature representation of Paludina ponderosa, except that it is decidedly umbilicated. The opercle is of a pale bright yellowish-brown color. 10 AMNICOLA LIMOSA, Say.. PLATE 1. FIGS. 5, 6. A. testa, lata, curta, late umbilicata, livescente; apertura subrotundata, labio in anfractum ultimum attingente. Long. 5 mm. SYNONYMS AND REFERENCES. PALUDINA LIMOSA, SAY. Jour. Acad. Nat. Sci., vol. i. p. 125. Anno 1817. Nich. Encyc. 3d Am. ed. 1819. P. PORATA,, ADAMS. Thompson's Hist, of Vermont, p. 2 ? Jl. PORATA, GOULD. Invert, of Mass., p. 229, fig. 157. Jl. LUSTRICA, HALD. In letters. DESCRIPTION. ANIMAL pale yellow, a dark band across the head immediately in front of the tentacles, around the base of which it turns and continues backwards along the side below the eye;* ten- tacles translucent, blackish along the margin. SHELL "conic, whirls slightly wrinkled, con- vex; suture profoundly indented; aperture oval, * Say and Gould both notice this character, which ap- pears to be constant. AMNICOLA LIMOSA. 11 nearly orbicular; labrum with the superior edge not appressed to the preceding whirl, but simply touching it; umbilicus rather large, rounded." COLOR corneous, with a bluish tinge. GEOGRAPHICAL DISTRIBUTION. Seems to occur from Maine to Pennsylvania and Ohio. "Ex- tremely numerous on the muddy shores of the rivers Delaware and Schuylkill, between high and low water marks." Say. OBSERVATIONS. " The aperture somewhat resembles that of a Valvata, to which genus it may probably be referrible." Say. It occurs on the Susque- hanna in company with A. decisa. In my cor- respondence I have used the name 'limoscf in accordance with the only definite character given, viz: "length A, breadth iV inch," which does not properly apply, the breadth being equal to the length ; but that I was wrong, I am con- vinced by several considerations, the principle being the comparison instituted by Say between his porata and limosa. A reference to my figures 5, 6, and 8, will show how closely these cor- respond. 12 AMNICOLA PALLIDA, Hald. PLATE 1. FIG. 7. A. testa conica, umbilicata, pallide ochracea, subhyalina; apertura ovata, lata, postice subangulata, in anfractum ultimum confluente. Long. 4 mm. SYNONYMS AND REFERENCES. A. PALLIDA) HALD. This work, December 1841. P. LUSTRICA, ADAMS. Hist, of Vermont, App. p. 2, 19. DESCRIPTION. Shell thin in texture, conical, rather robust, composed of 4 convex whirls, separated by a well marked suture; spire obtuse, rather longer than the aperture; umbilicus narrow; aperture ovate-orbicular, forming an angle posteriorly; a small portion of the labium confluent with the body whirl posteriorly. COLOR pale ochraceous, translucent. GEOGRAPHICAL DISTRIBUTION. Inhabits Lake Champlain. Prof. Adams. AMNICOLA FOR AT A. 13 OBSERVATIONS. Intermediate between lustrica and porata. It is not as short and transverse as the former, which, moreover, is widely umbilicate and has the aperture regularly rounded posteriorly. Ac- cording to the description of Professor Adams, the labium sometimes scarcely touches the body of the shell. The spire is comparatively longer than in porata, the outline less transverse, and the aperture not orbicular. AMNICOLA PORATA, Say. PLATE 1. FIG. 8. A. test lata, curta, late umbilicata; anfractibus 4$ cylin- draceis, lineis obsoletis eleVatis revolventibus; aperturk rotundatiL Long. 5^ mm. SYNONYMS AND REFERENCES. P. PORATA, SAY. Journal Acad. Nat. Sci., vol. ii. p. 174. DESCRIPTION. SHELL "obtusely conic or subglobose; volu- 14 AMNICOLA PORATA. tions four, convex, obsoletely wrinkled across; spire obtuse; labrum and labium equally round- ed, meeting above in a subacute angle; the upper edge of the latter appressed to the pre- ceding whirl; umbilicus very distinct." Say. COLOR pale ochraceous. GEOGRAPHICAL DISTRIBUTION. Inhabits Cayuga lake. Say. OBSERVATIONS. "Rather larger and more globose than P. limosa, to which it is allied, and has a more dis- tinct umbilicus. It resembles P. dedpiens of Ferussac, but is much less acute, and rather smaller." Say. This shell so much resembles a Valvata, that it is to be regretted that living or operculated individuals have not yet been observed. 15 AMNICOLA GALBANA, Hold. PLATE 1. FIG. 9. A. testa (inter DECISAM et PALLIDAM intermedia) conica, solidula, laevi, umbilicata, apertura late ovata. Long. 4 mm. DESCRIPTION. SHELL conical, smooth, shining, composed of 4J not very convex whirls, having the lines of growth very fine: base with a narrow umbilic: aperture nearly circular, slightly produced in an angle posteriorly; labium slightly thickened; a small portion of it, which is rectilinear, in slight contact with the body whirl. COLOR . . . bleached and chalky. GEOGRAPHICAL DISTRIBUTION. Occurs fossil in the freshwater newest tertiary deposit in Sussex county, New Jersey. OBSERVATIONS. Figure 3 of A. decisa is a tolerably good re- presentation of this shell, which differs in having a small, well defined umbilic. 16 AMNICOLA LUSTRICA, Say. SYNONYMS AND REFERENCES. PALUDINA LUSTRICA, SAY. Journ. Acad. Nat. Sci., vol. ii. p. 175. DESCRIPTION. SHELL "conic; whorls slightly wrinkled, con- vex; suture profoundly indented; aperture oval, nearly orbicular; labrum with the superior edge not appressed to the preceding whirl, but simply touching it; umbilicus rather large, rounded. "Length less than T V inch. "Cabinet of the Academy." "The smallest species I have seen.* The aperture somewhat resembles that of a Valvata, to which genus it may probably be referrible. Mr. Jessup obtained two specimens on the shores of Cayuga lake." Say. * But one of the two specimens referred to by Say is perfect, and may be seen in the Cabinet of the Academy of Natural Sciences, Philadelphia. It is a slender pale yel- lowish-brown shell, having four volutions, and is 5 or 6 millimetres long. It is closely allied to A. lapidaria, of which it may possibly be the young. 17 AMNICOLA GRANUM, Say. A. (LIMOS^E affinis) testa minuta, conica, curta, late um- bilicata; apertura rotundata. Long. 2 mm. SYNONYMS AND REFERENCES. PALUDINA GRANA, SAY. J. Acad. Nat. Sci., vol. ii. p. 378. DESCRIPTION. SHELL "conic-ovate; whorls not perceptibly wrinkled, convex; suture deeply impressed; aperture orbicular, hardly angulated above; labium with the superior edge appressed to the surface of the penultimate volution; umbilicus rather small, profound." " This very small species is found in plenty in the fish ponds at Harrowgate, [near Philadel- phia,] crawling on the dead leaves which have fallen to the bottom of the water. It resembles P. lustrica, but is a smaller, less elongated shell, and the superior portion of the labium is not an unaltered continuation of the lips as in that shell, but is appressed to the surface of the penultimate whorl in the usual manner of cal- careous deposition upon that part." Say. E 3 18 AMNICOLA LAPIDARIA, Say. PLATE 1. FIG. 10. A. testa elongata, ochraceo-brunnea, perforata; apertura ovata, subangulata; labio subarcuato, in anfractum ultimum posito. Long. 6 mm. SYNONYMS AND REFERENCES. P. LAPIDARIA, SAY. Nich. Encyc. 3d Am. ed. No. 2. DESCRIPTION. ANIMAL "not so long as the shell, pale; head elongated into a rostrum as long as the tenta- cula, and emarginate at tip; tentacula 2 filiform, acuminated at tip, short; eyes prominent, situ- ated at the external or posterior base of the tentacula; base or foot of the animal dilated, oval, obtuse before and behind." SHELL "turreted, subumbilicate, with 6 volu- tions which are obsoletely wrinkled across; suture impressed; aperture longitudinal ovate orbicular, operculated, rather more than one- third the length of the shell. Length about J inch." AMNICOLA SAY ANA. 19 OBSERVATIONS. COLOR pale brown. GEOGRAPHICAL DISTRIBUTION. Appears to oc- cur both east and west of the Allegeny moun- tains. "Found under stones, &c. in moist situations, on the margins of rivers. Like Lymnaea and Planorbis, this animal possesses the faculty of crawling on the surface of the water in a re- versed position, the shell downward." Say. AMNICOLA SAYANA, Anthony. PLATE 1. FIG. 11. A. test elongatula, umbilical, ochracea, nitida, diaphana; anfractibus 6 cylindraceis; apertura rotunda, labro sub- appresso in parte posteriori. Long. 5 mm. SYNONYMS AND REFERENCES. AMNICOLA SAYANA, ANTHONY. In letters. CVCLOSTOMA CINCINNATIENSE, LEA. Tr. Am. Phil. Soc. 2nd ser., vol. viii. p. 229, pi. 6, fig. 62. 20 AMNICOLA SAYANA. DESCRIPTION. SHELL lengthened, conic, composed of 6 very convex shining whirls; suture strongly impress- ed; lines of growth very fine; base with a nar- row umbilic: aperture suborbicular; the labium slightly flattened, a small portion of it in con- tact with the body whirl. COLOR bright yellowish-brown, translucent. GEOGRAPHICAL DISTRIBUTION. Inhabits south- western Ohio. HABITS. "It is found on wet earth and roots of trees on the margin of a small stream near Cincinnati." Lea. OBSERVATIONS. This handsome species was sent to me by Mr. Anthony, under the proposed specific name sayana, which I have adopted. In habit it ap- pears to agree with lapidaria, a species which Say's description justifies us in referring to the genus Amnicola. 21 AMNICOLA NICLINIANA, Lea. PLATE 1. FIG. 12. A. testa, elongato-conica, obscura, subperforata, aper- tura pallida; labio subrectilineari, appresso. Long 3 mm. SYNONYMS AND REFERENCES. P. NICKLINIANA, LEA. Tr. Am. Phil. Soc., vol. vi. p. 92, pi. 23, fig. 109. DESCRIPTION. SHELL slender conic, whirls 4, convex; aper- ture ovate, labium appressed so as to leave a narrow umbilical fissure. COLOR greenish, covered with a black coating. GEOGRAPHICAL DISTRIBUTION. Inhabits the Warm springs of Virginia. OBSERVATIONS. Figured from an authentic specimen for which I am indebted to Mr. Lea. It bears a very close resemblance to the young of the next species. 22 AMNICOLA ATTENUATA, Hald. PLATE 1. FIG. 13. A testa, columnari, vix perforata, sutura profunda. Long. 7 mm. SYNONYMS AND REFERENCES. A. ATTENUATA, HALD. J. Acad. Nat. Sci., vol. viii.p. 200. DESCRIPTION. ANIMAL black. SHELL unusually long, slender, with 6 or 7 obliquely revolving, very convex whirls, sepa- rated by a deep suture; aperture small, ovate, with the peritreme level and continuous; labium in contact with the body whirl, leaving scarcely any perforation. COLOR pale green beneath an extraneous coat- ing of black. GEOGRAPHICAL DISTRIBUTION. Taken from a spring in Montgomery county, Virginia, con- nected with Roanoke river. I am not confident that this is not the adult of nicliniana, as there is a very close resemblance between that shell and the young of this species when it has but 4 volutions. In the latter, the aperture appears to be rather contracted. 23 AMNICOLA TENUIPES, Cauper. PLATE 1. FIGS. 14, 15. A. testa elongatula, flavo-brunnea, subperfbrata; anfrac- tibus 5 planiusculis, sutura inconspicua, apertura ovata, labio obsolete. Long. 4 mm. DESCRIPTION. ANIMAL "with the head proboscidiform, sub- bifid, subcylindrical; foot strap-shaped, anterior portion extending laterally, and emarginate be- fore: tentacles setaceous; eyes at the external base of the tentacles; color, except the head and eyes, mottled white. SHELL " small, H lin. long, subumbilicated, oblong-ovate, turreted, thin, smooth, lines of growth very slightly marked; color light brown; volutions 5, suture slightly impressed: aperture ovate, oblong, angulated above, rounded at base; labrum simple, sharp. HABITS. "Found in the rice-field ditches at Hopeton, Georgia: movement active, made by the joint action of the head and foot, the head advancing before the foot: floats on the surface of the water in an inverted position." 24 AMNICOLA TENUIPES. OBSERVATIONS. The above account of a very interesting spe- cies has been obligingly furnished, together with a drawing of the animal, by J. Hamilton Couper, Esq., to whose exertions science is much in- debted. The species is remarkable for having an unusually slender foot. Amnicola orbiculata, Lea. Proceed. Am. Phil. Soc., ii. 34. "Testa orbicular!, subtenui, luteola, laevi, um- bilicata; spira brevi; suturis valde impressis; anfrac- tibus quinis, inflatis; apertura magna, rotunda. Hab. Springfield, Ohio, and Schuylkill? near Philadelphia." A. parva, Lea. Ib. " Testa obtuso-conica, subtenui, luteola, Isevi, umbilicata; spira brevi; suturis impressis; anfractibus quaternis, inflatis; apertura, magna, sub- rotunda. Hab. Springfield, Ohio." A. obtusa, Lea. (Paludina.) Am. Phil. Tr., second series, vol. ix. p. 13. "Testa subcylindracea, subtenui, tenebroso-viridi, laevi, minute perforata; spira brevi, ad apicem valde obtusa; suturis impressis; anfractibus quaternis, convexis; apertura parva, subrotunda. Hab. Ohio. Diam. .07, length .10 of an inch." *^* Several errors occur in the names upon the plate of Amnicola (lettered from recollection) which should be cor- rected. 444 4 4 4 A i__3 A f'lMOSiL, S. 4 A CINCINNATIENSIS, A 5_6 A L-US--AI.e^i. S T. ^ PALLIDA, H. 8 yl PORATA. S 9 ^ GALBANA. H 10 ^ CAPIDARIA, S 11. ^. S^KIW^, H 12 4 NICKLINIANA. Lea 13 ^ ELONGATA. H H_15 ^ TENUIPES, CoTJJ>BT- HelaiL E Lawson. 3el et col Alex Larson Sc GENUS PALUDINA, Lamarck. PLATE 1. FIG. 1. Testa conoidea: apertura Integra, ovata: anfractibus con- vexis: marginibus connexis, acutis: operculum corneum. SYNONYMS AND REFERENCES. HELIX, LINNAEUS, GMELIN, DILLWIN. TURBO. BUCCINUM. VIVIPARA. CYCLOSTOMA. NERITA, MULLER, SCHROTER. BULIMUS, (BULINUS,) PoiRET. PALUDINA, LAMARCK. An. sans Vert., vol. viii. p. 509. SOWERBY. Genera of Shells. CUVIER. An. du Mus., vol. xi. p. 170 Memoires pour servir a L'Histoire et a L'Anatomie des Mollusques. Anno 1817. DESCRIPTION. ANIMAL with the head short and truncated, extending a little beyond the shell: rostrum very small: mouth terminal, furnished with two lateral jaws: tentacles slender and subulate, the eyes situated upon an enlargement of their Fl 2 PALUDINA. external base: the foot is a thin broad lingui- form disk, longer than the shell, much extended anteriorly, and bearing an opercle upon its upper posterior surface: mantle simple. SHELL conoid, whirls convex, modifying the spiral cavity: aperture ovate or subrotund, widest anteriorly, the margins united, sharp, and never reflected: aperture closed with a thin corneous opercle, of which the lines of increase are generally concentric. EXAMPLE. Paludina decisa.* OBSERVATIONS. "The name of the genus was adopted by Lamarck, from Bruguiere, but Montfort applied to it the name of Viviparus, which is retained by Blainville in his plate, though in the text he adopts that of Paludina." Say. As Lamarck was the first to perceive and define the natural limits of the genus, as characterized by him, he must be cited as authority for it. * This species is chosen as an example of the genus, because the accompanying description of the animal has been drawn principally from it. This mode will be pursued with the subsequent genera, when reference to the entire animals of typical species cannot be made. PALUDINA. The animals of this genus are of sluggish habits; they feed upon living or decayed vege- table matter, and respire water, in which they live entirely, generally preferring a bottom of soft mud, upon which they are well adapted for progression, on account of the great extent and flexibility of the foot. Its extension in front prevents them from taking food, except when at rest. They prefer nearly stagnant waters, or rivers with sluggish currents. The Paludinse are viviparous, depositing the young in the spring, which have lain in the ovaries during the winter. The sexes are said to be distinct. The genus is here restricted by the omission of the small oviparous species,* with subspiral opercles, and the foot short anteriorly. The shells of some species make so near an approach to those of certain Ampullarise, that it is difficult to distinguish them. In this case, an aperture narrowed posteriorly, and a length- ened spire, will generally indicate the genus Paludina sufficiently for ordinary purposes. * As P. lustrica, Say, which is the type of a new genus, (AMNICOLA, Gould and Hal.) suggested by Dr. Gould. PALUDINA DECISA, Say. PLATE 1. P. testa ventricoso-conica, tenui, pallide virente, laevi- gata: spira elongata, apice obtusa: anfractibus valde con- vexis: apertura subovata, postice angulata: sutura valde impressa. SYNONYMS AND REFERENCES. LISTER, Conch., pi. cxxvii. fig. 27. Cochlea virginiana e flavo viridescens, non fasciata. PETIVER, Gazophyl., pi. cvi. fig. 18. P. DECISA) SAY. Nich. Encyc., (Amer. ed.,) art. Conch., pi. ii. fig. 6. Anno 1818. Am. Conch., pi. x. fig. 1. CHEMNITZ, vol. ix., pi. cxxxii. fig. 1184.? VALENCIENNES. Receuil d'Obs. de Zool., par Humb. et Bonpl., vol. ii. p. 253. P. limosa, Say. P. CORNEA, 1 VAL. op. cit. DESHAYES in Lam., vol. viii. p. 516, an P. ponderosa junior ? P. HETEROSTROPHA, KlRTLAND. Ohio Geol. Rep., p. 200. DESCRIPTION. ANIMAL light cream-yellow, or bluish, marked with numerous orange spots upon the head, tentacles, and foot; the under surface of the PALUDINA DECISA. D last more finely dotted: tentacles dark above; eyes black and conspicuous: foot translucent, very large anteriorly, ending square, but slightly emarginate in the centre: rostrum small, and scarcely projected beyond the edge of the shell. The centre of the under surface of the foot is marked with light reticulated lines, which are radiated towards the edges. SHELL thin, subconic, and polished, with six convex whirls: spire lengthened, having the apex rounded: aperture wide and pyriform; labrum meeting the body whirl at an angle: suture deep: lines of growth very fine: spiral striae minute or obsolete. COLOR of the shell bright green, or yellowish- green; inside bluish-white. GEOGRAPHICAL DISTRIBUTION. The streams of New Jersey, the Delaware, Schuylkill, and rarely, the Susquehanna. Common throughout New England, Dr. A. A. Gould. Ohio, J. G. Anthony. "The species is very common in various parts of the Union," Say. Dr. Wm. Blanding has given me specimens which he collected from the Mississippi in Iowa Terri- tory, and from Fox river, between Galena and Chicago. It occurs in the Nolachucky and O PALUDINA DECISA. Tennessee rivers, on the south shore of Lake Michigan, and Mr. R. C. Taylor brought speci- mens from the "Four Lakes" of the North-west Territory. OBSERVATIONS. The quite young have a very low spire, a globular form, and the aperture very wide, nearly equalling half the entire lower surface in area. The soft parts are semitransparent, without any orange spots. The young are ex- cluded in March, when the shells are 0.14 or 0.15 of an inch in length, composed of rather less than three entire whirls. In autumn, pre- vious to the sinking of the animals into the mud to hybernate, the ovaries of the female (extending within the apex of the shell) will be found to contain many young, apparently in as perfect a state as when excluded in the spring. Dr. Gould (MS.) states that the shell is bristled with filaments, which are visible when in the water; particularly upon half grown indi- viduals. Deshayes does not admit this species in his edition of Lamarck, but places the name (with a question) among the synonyms of P. ponde- PALUDINA DECISA. 7 rosa. It must be confessed that the two are nearly allied, but I think it would be immature to unite them until a complete series of the shells of both could be shown, which would indicate the passage of the adult of one into that of the other species. P. decisa has a thinner shell and narrower aperture; nor are the lines of growth so suddenly recurvent as in P. ponderosa. The young have a near resem- blance, but the larger the decisa grows the less is the resemblance apparent. Valenciennes cites Say's description of P. limosa (Journal of the Academy, vol. i. p. 125) for this species; and, leaving size out of the question, descriptions of the two shells would very nearly correspond. M. Valenciennes' spe- cimens are about an inch in length, the truo limosa being no longer than 0.15 of an inch. This species has been found heterostrophe in Ohio, the Delaware, and in Vermont; and upon this variety Professor Kirtland has found- ed his species. REFERENCE TO PLATE 1. Fig. 1 represents an animal from the Susquehanna, where the shells are shorter than usual. Fig. 2 is taken 8 PALUDINA SUBCARINATA. from a Schuylkill shell, of which a represents the opercle. Fig. 3 is from a Massachusetts specimen. Fig. 4 is from a reversed Ohio specimen in the cabinet of Mr. Lea. Figs. 5 and 6 represent the young of different ages. PALUDINA SUBCARINATA, Say. PLATE 2. P. testa elongata, tenui, apice acutissima, (interdum erosa,) pallide fusco-virente: anfractibus quinis vel senis, valde convexis, transversim striata: sutura valde impressa: apertura ovata, postice rotundata. SYNONYMS AND REFERENCES. P. SUBCARINATA, SAY. Nich. Encyc., (Amer. ed.) art. Conch., pi. i. fig. 7. P. CARINATA, VALEN. Rec. d'Obs. de Zool., par Humb. et Bonpl. DESCRIPTION. ANIMAL with the foot translucent, the sides parallel, the front truncated, and the posterior extremity obtusely rounded. The general co- lour is dark grey, dotted with light orange. SHELL conoid, elongated, thin and translu- PALUDINA SUBCARINATA. cent, with from four to six ventricose volutions, which are covered with numerous fine trans- verse elevated striae: apex pointed: suture deeply impressed and canaliculate: aperture regularly ovate, rounded posteriorly: peristome entire. The later additions of the opercle are concen- tric, whilst the centre is subspiral. COLOR of the outside very light brownish- green; inside bluish-white. GEOGRAPHICAL DISTRIBUTION. Found in the Delaware, Schuylkill, and Susquehanna rivers: near Cincinnati, Ohio, J. G. Anthony. OBSERVATIONS. This species is closely allied to the preced- ing, both in external form and general habits, so that the natural history of one is that of the other. The shell may be distinguished from that of P. decisa by the subrotund aperture, pointed apex, elevated striae, and dull exterior. Those inhabiting running waters have the shell thick and opaque, with the apex eroded. The orange spots upon the animal are lighter and smaller than in the preceding species. The young, when first excluded throughout the spring and summer, are spirally striated, F 2 10 PALUDINA INTEGRA. and have less than three complete whirls. The shell is more lengthened and much less ventri- cose than the young of P. decisa. REFERENCE TO PLATE 2. Figs. 1 and 2 represent a very large individual, of which la is the opercle. Figs. 3 and 4 are views of a more characteristic specimen. Fig. 5 is the very young. PALUDINA INTEGRA, Say. PLATE 3. P. testa elongata, fusca vel olivacea: anfractibus quinis vel senis, convexis: sutura valde impressa: apertura inte- gra, postice obtusa vel rotundata. SYNONYMS AND REFERENCES. P. INTEGRA, SAY. Jour. Acad. Nat. Sci., vol. ii. p. 174, DESCRIPTION. "SHELL olivaceous, pale, conic: whirls six, wrinkled across: spire rather elongated, entire at the apex: suture profoundly indented: aper- ture sub-ovate, less than half the length of the shell." Say. PALUDINA INTEGRA. 11 "Inhabits the waters of the Missouri. "Length 1-4 of an inch. [1.4 in.? or 1} in.?] "Very much resembles P. decisa; the spire, however, is more elongated, and never trun- cated at the apex, but always acute." Say. GEOGRAPHICAL DISTRIBUTION. Inhabits the Santee canal, South Carolina, (fig. 3,) T. A. Conrad: Ohio, (figs. 1, 2,) J. G. Anthony: the Mississippi, in Iowa Territory, (fig. 4,) Dr. W. Blanding. OBSERVATIONS. I have made use of Say's description and remarks, as this is a species ? about which there is some uncertainty. The shells here figured are generally received as P. integra, although every one must have remarked the discrepancy between their size and that given above. Mr. Say's time, however, was too valuable to be spent in searching for large specimens; we accordingly find that he described his Paludina subcarinata from a specimen having three whirls; and figured Melania virginica from one with but five; whilst good specimens of both shells have just twice the number of whirls given. It is possible that the size, as given in 12 PALUDINA INTEGRA. the original description, is a typographical error. This may be a variety of P. decisa; but as the characters appear to be constant, it may stand as a species until a more extended exa- mination of specimens can be made. Deshayes has truly remarked, that specific distinctions exist, not so much in the distinctness, as in the permanency of the characters; and that it is sometimes necessary to make extensive com- parisons before just decisions can be made.* REFERENCE TO PLATE 3. Figs. 2 and 3 represent a very large individual; 1 is the usual size and appearance; 4, a strongly marked variety; 5, the young; and , an opercle. * His words are "il faut, pour eviter une autre source d'erreurs, avoir a sa disposition une collection tres con- siderable par le nombre des especes et celui des individus appartenant a chacune d'elles, la valeur d'un caractere specifique residant plutot dans sa Constance, malgre sa faiblesse, que dans sa grandeur, et cette Constance ne peut etre constatee que par 1'examen d'un grand nombre d'indi- vidus provenant de localites diverses." Lam. An. sans Vert., torn. vii. p. 329. Anno 1836. 13 PALUDINA PONDEROSA, Say. PLATE 4. P. testa ponderosa, subconica, laevigata; striis transversis minutissime corrugatis: apice obtusa: anfractibus convexis: sutura valde impressa: lineis longitudinalibus recurvatis: apertura ovato-oblonga. SYNONYMS AND REFERENCES. P. PONDEROSA, SAY. Jour. Acad. Nat. Sc., vol. ii. p. 173. Amer. Conchology, pi. 30, fig. 1. SOWERBY'S Genera of Shells, fig. 2. DESHAYES' LAMARCK, vol. viii. p. 516. DESCRIPTION. SHELL ponderous, subconic, and polished, having from six to seven complete whirls: spire lengthened: suture deeply impressed, and ca- naliculate: aperture oblong ovate, narrowed and rounded posteriorly: labium thickened, and conspicuous: lines of growth undeviating until near their anterior extremity, where they are recurvent; labrum much advanced at this part: surface with very fine transverse wavy strise, 14 PALUDINA PONDEROSA. and occasionally banded with colors a little lighter or darker than that of the general sur- face: opercle thin, oblong ovate, with the lines of growth concentric. COLOR of the shell light green (when young) to dark olivaceous externally, and bluish-white within. VARIETY A. The shell does not exceed an inch in length; the transverse wavy striae are obsolete; the spire is low, and truncate-eroded, and the labium very much thickened posteriorly. Specimens were given to me by Mr. Conrad, who found them in the Alabama river. GEOGRAPHICAL DISTRIBUTION. This, the larg- est of our species, inhabits the Wabash, Ohio, and other western rivers. "Paludina ponderosa seems a common inhabitant of all the rivers of the west, from the northern districts of Indiana and Illinois, to the waters of the Tennessee valley." Conrad, New Fresh Water Shells, p. 12. OBSERVATIONS. Deshayes thinks this species might as well be placed in the genus Ampullaria, whilst Say believed it to be allied to Melania. "On pour- PALUDINA GENICULA. 15 rait aussi bien placer cette coquille parmi les Ampullaires que parmi les Paludines, son ou- verture se trouvant plus allongee et plus etroite que dans la plupart des especes de ce dernier genre." Deshayes. I regret that I am unable to give a figure, or at least a description of the animal, of this fine species. REFERENCE TO PLATE 4. The inferior surface of two shells, an opercle, and the very young are represented. The specimens figured are not of the largest size. PALUDINA GENICULA, Conrad. PLATE 5. P. testa subovalis, spira elongata: anfractibus quaternis scalariformis, postice angulatis. SYNONYMS AND REFERENCES. P. GENICULA, CON. N. F. w. Shells, p. 48, pi. 8, fig. 3. DESCRIPTION. SHELL suboval, composed of four scalariform whirls, which are angulated posteriorly: spire 16 PALUDINA GENICULA. elevated, diminishing rapidly: apex obtuse: lines of growth fine and distinctly marked: surface polished: aperture more than half the length of the shell. The opercle has the lines of accre- tion concentric. COLOR of the shell greenish; aperture bluish. OBSERVATIONS. A single shell of this species was found by Mr. Conrad in Flint river, Georgia. This unique specimen is now in the cabinet of Mr. Poulson. REFERENCE TO PLATE 5. Figures 1 and 2 are views of the upper and lower sur- faces of the shell, of which a represents the opercle. The latter, it will be observed, had been broken, and was sub- sequently repaired by the animal. 17 PALUDINA VIVIPARA, Lin. PLATE 6. P. testa ventricosa, subperforata, tenui, subdiaphana, fusco-virente: anfractibus quinis, convexis: spira elongata, apice obtuso: fasciis transversis fusco-rubris: sutura valde impressa: apertura rotundata, intus transversim fasciata. SYNONYMS AND REFERENCES. LISTER, Conch., pi. cxxvi. fig. 26. HELIX VIVIPARA, LINN.EUS, GMELIN, p. 3646, No. 105. NERITA VIVIPARA, MULLER. Vermes, p. 182, No. 370. CHEMNITZ, vol. ix., pi. cxxxii. fig. 1180, 1181. PALUDINA VIVIPARA, LAMARCK. An. sans Vert., vol. viii. p. 511. SAY, Nich. Encyc. (Amer. ed.) art. Conch., pi. ii. fig. 5. " American Conchology, pi. x. the two side figures. P. LINEATA, VALENCIENNES. Rec. d'Obs. de Zool., etc., par Humboldt et Bonpland, vol. ii. p. 255. DESCRIPTION. SHELL subconic, ventricose, thin, and slightly translucent; with five inflated volutions: there are several reddish bands visible within and F3 18 PALUDINA VIVIPARA. without: spire lengthened, apex scarcely round- ed, suture deeply impressed: aperture sub- rotund. COLOR of the outside greenish, or brown; of the inside, whitish. GEOGRAPHICAL DISTRIBUTION. Say's speci- mens were obtained from the St. John's river in Florida; Mrs. Say has sent me specimens from the Wabash, and Mr. Conrad from near Tuscambia, Alabama; Mr. Anthony has been informed of its existence near St. Louis, Mis- souri, and in Michigan: Valenciennes' speci- mens are from Lake Erie: Cuba is given as the locality of a specimen in the cabinet of the Academy of Natural Sciences. OBSERVATIONS. This is one of the very few species common to Europe and North America. A comparison of the soft parts may be necessary to prove those found on different sides of the Atlantic to be identical; but where there is not a sufficient difference in the shells to establish varieties, it is not probable that the soft parts would pre- sent distinctive specific characters. Deshayes does not cite Say's figures among PALUDINA VIVIPARA. 19 the great number of synonyms which he has added to those of Lamarck; thinking perhaps that this might be a distinct species. He had access to the American Conchology, as he admits several species from it, and cites a figure from the same plate upon which P. vivipara stands. Being the first Paludina known to naturalists; the fact that it is viviparous attracted early attention, and became the foundation of its specific name. I believe every species of true Paludina will be found to be viviparous (or ovo- viviparous) and know of eight distinct species which are. EXPLANATION OF PLATE 6. Fig. la represents the opercle belonging to 1 and 2, (from the Wabash); fig. 6 is the natural size of a young shell taken from the former, which had been dried with the animal enclosed; fig. 5 is a thin light coloured half- grown shell from Alabama; and figs. 3 and 4 a variety with a lengthened spire, copied from Say's figure, the original specimen being probably from Florida. The shells from the Wabash have a smaller and more circular aperture than those from the South; and the half-grown have a greater resemblance to the adult in form and color. I have cited Linna3us as authority for the preceding species, because he was the first to describe it under the 20 PALUDINA VIVIPARA. adopted specific name. The author who institutes and names a species, should always be cited as the earliest authority for it, under whatever genus or other division it may be placed by later systematists. Species are perma- nent, but other divisions must be modified from time to time, as opportunities to gain the requisite information occur; and it appears to be a gross act of injustice to the earlier zoologists, to leave them nothing for their labors, because they could not take advantage of information ac- quired after their time. One author thinks he does ample justice to his predecessor, by citing him among the synonyms; but here he should place his own name, if he thinks it sufficiently important to occupy a place, merely because he has the very trifling merit of placing a well known animal or plant in its appropriate modern genus. In some works, but few synonyms are cited, and in such, the founder of a species might be omitted entirely. It is true, that Linnaeus never described a shell under the name of Paludina; but he specified one as vivipara; and no one would suppose that he formed the genus, should his name be placed after the species, so that there would not be a cause of error. On the contrary, when we find a modern author citing himself incidentally, (for a European bird, for instance,) we might be led to wonder, why a species had remained so long uncharacterized. Thus, besides de- priving us of the power to know whether a species has been long known, or recently described; there is a source of error laid open, which could scarcely exist, if the juster course were pursued. This is subject to no abuses, whilst the self-appropriating system affords every facility for acts of injustice. Unnecessary divisions are made, apparently PALUDINA VIVIPARA. 21 with no other object; and the pretender, who wishes to be cited as the authority for placing certain species in certain genera, has only to prowl over the works of naturalists of high standing, until he finds something which will answer his purpose. Thus he may discover that Paludina dissi- milis is an Anculosa pretend that the genus Exogyra is untenable, (which will enable him to place Ostrea or Chama before, and his own name after, all the species) or that of the synonyms Lytta and Cantharis, (the former being pre- ferred by the Germans, the latter by English entomolo- gists,) Say chose the worst for his L. Nuttalli, which can accordingly be changed to Cantharis Nuttalli; or, all the species of Cantharis may be changed back to Lytta, with- out the trouble of going to "the base of the Rocky Moun- tains" for species. The various changes in nomenclature can be placed with propriety only in the list of synonyms, and it is giving what is not wanted, to place the name of him who has done the least for a species, after it; instead of his, to whom we owe it; especially when it is mentioned incidentally, without immediate reference to the original synonym. It is better to have a single original authority for a species, cited throughout all works, than to have a different one for every author who chooses to publish upon it. An interme- diate plan might be adopted, which would place "of authors," (Auc.) after species like the above; or to cite the original authority with the later one, thus: Paludina vivi- para, Lin., Lam. I might cite authorities for my own views, but they are divided; the majority perhaps, holding oppo- site opinions; (as many of them are more or less interested 22 PALUDINA VIVIPARA. in the appropriating system;) but injustice should not be sanctioned on any authority. Could the good old Swede have foreseen the havoc destined to be made among his species, he would certainly have placed the founders of the modern credit system among his Damnati. Thus in the dismemberment of the Simiadse, not a single genus was left under his appropriate name, Simia; and all the species were transferred, as a matter of course.* The original spirit of all this is a desire to be credited with something, however trifling; and as original research is difficult, some method had to be devised to abstract from the well filled stores of the older authors; and in such a manner as not to excite suspicion; just as influential crimi- nals who undergo a regular trial, are sometimes set free by a preconcerted "flaw in the indictment." The pro- ceedings, in both cases, have an appearance of justice, but nothing more. The original author loses his species, whilst the act of his successor is about as creditable as the productions of those painters who, according to Reynolds, "if they have a history or a family piece to paint, the first thing they do is to look over their common-place book, containing sketches which they have stolen from various pictures; then they search their prints over and pilfer one * It is conceded by all, that the Nerita urcea of Miiller, (subse- quently named Ampullaria rugosa by Lamarck,) should be called Ampullaria urcea; and as Lamarck cites Miiller's name as a synonym, no one can claim the discovery of the identity of the two: we accordingly find that no author has ventured to give him- self as authority for the species. PALUDINA GEORGIANA. 23 figure from one print, and another from a second," which (he might have added) enables them to get their names into the catalogues, whilst not a thought is bestowed on those to whom the originals owe their existence. PALUDINA GEORGIANA, Lea. PLATE 7. FIGS. 1, 2. P. testa elongata, ventricosa, anfractibus quaternis vel quinis, convexis: sutura impressa: apertura rotundata, postice angulata. SYNONYMS AND REFERENCES. P. GEORGIANA, LEA. Transactions of the Am. Phil. Soc., new series, vol. v. p. 116, pi. xix. fig. 85. - DESCRIPTION. SHELL elongated, ventricose, thin and smooth; with four or five convex volutions: suture deep, and well marked: aperture nearly round, angu- lated posteriorly. COLOR of the outside green, inside whitish. GEOGRAPHICAL DISTRIBUTION. Found as yet only at Hopeton, near Darien, Georgia. Lea. 24 PALUDINA BENGALENSIS. OBSERVATIONS. This species is most nearly allied to P. decisa, Say; from which it may be distinguish- ed by the subrotund aperture; and from P. vivi- para, by the want of the rufous bands. That it is a distinct species, I have not the least doubt. I am indebted to Mr. Lea for the use of his original specimen to figure and describe. PALUDINA BENGALENSIS, Lam. PLATE 7. FIGS. 3, 4. P. testa conica, tenui, acuta, pallide virente, trans- versim fusco-lineata: apertura subrotundata. SYNONYMS AND REFERENCES. P. BENGALENSIS, LAM. An. sans vert., vol. viii. p. 513. P. FASCIATA, BOWD. Elem. of Conch., pi. ix. fig. 15.* DESHAYES Encyc. Meth. vers, vol. iii. p. 691, No. 3.* " Voy. aux Ind. par Bel. Zool., p. 419, No. 9, pi. i. figs. 14, 15.* P. ELONGATA, SwAiNsoN. Zool. illustr., first series, pi. xcviii. Anno 1821 2. Not the P. elongata of Sowerby. P. MULTILINEATA, SAY. Disseminator, Aug. 12th, 1829. p. 245. Mrs. Say's reprint, p. 21. * Cited by Deshayes. PALUDINA BENGALENSIS. 25 DESCRIPTION. SHELL lengthened, conic, and polished; com- posed of six or seven convex whirls, the sur- face of which is covered with minute transverse wrinkles, and numerous narrow spiral bands: apex pointed; suture deep; lines of accretion very fine; aperture regularly rounded, produced posteriorly. COLOR light green, often passing into brown- ish; the spiral bands are fuscous, and the inside white. OBSERVATIONS. "Captain Leconte presented me with a shell which, he informed me, he found in the river St. John, Florida. I described it nearly four years since under the name of multilineata; but recently, being about to publish it, on a more attentive examination and comparison with a specimen of the elongata from Calcutta, I have concluded that it varies from that specimen only in having the umbilicus a little smaller." Say. The shell figured is in the collection of the Academy of Natural Sciences, where it was F 4 26 PALUDINA BENGALENSIS. placed by Mrs. Say. There appears to be no reason to doubt the locality of this specimen; at any rate, Say was satisfied upon this point, and I accordingly admit it as indigenous, upon his authority. I have compared the original specimen with shells from Calcutta, and find that it differs as little from them, as they do from each other. It is smaller than the foreign specimens, but I think a larger native shell was mislaid, or placed accidentally among the foreign ones, in the same collection; so that, rather than commit an error, I have chosen the reputed American example for my illustra- tion. If this is not the Bengalensis of La- marck, it must have the name given to it by Say; that of Swainson having been previously given to a fossil species. PALUDINA CARINATA, Val PLATE 8. P. "testa conoidea, tenui, subdiaphana, viridi; anfrac- tibus quinis, longitudinaliter striatis, et transversim cari- natis." VaL PALUDINA CARINATA. 27 SYNONYMS AND REFERENCES. PALUDINA CARINATA, VALENCIENNES, in Rec. d'Obs. de Zoologie, &c., par Humboldt et Bonpland, vol. ii. p. 252, pi. Ivi. fig. 2, a, b. DESCRIPTION. SHELL conoid subdiaphanous and slightly umbilicated; having five convex turns which are longitudinally striated, and transversely carinated, with four elevated lines, of which the first and third are larger than the second and fourth: aperture angulated posteriorly, nearly circular, but having the longitudinal greater than the transverse diameter; the peristome is slightly thickened, and the edge is not sharp. COLOR green; with a tinge of brown upon the last whirl; aperture white. GEOGRAPHICAL DISTRIBUTION. Mexico. OBSERVATIONS. This species was discovered by Humboldt in Mexico, and is admitted on the authority of Valenciennes, who wrote the conchological part of the work cited; and from which I have taken the above descriptions, and my plate of the shell. 28 PALUDINA SUBPURPUREA, Say. PLATE 9. P. testa conica, subpurpurea: spira elongata, apice sub- convexo: anfractibus quinis, convexis: sutura impressa: apertura ovato-rotundata. SYNONYMS AND REFERENCES. P. SUBPURPUREA, SAY. Disseminator, vol. ii. p. 245. Mrs. Say's reprint, p. 21. Am. Conch., pi. xxx. fig. 2. DESCRIPTION. ANIMAL "very pale bluish, with minute yel- low points, particularly on the rostrum, tenta- cula, and prominent respiratory tube, which is as long as the tentacular eyes on the exterior side of the tentacula,* near the middle of their length: the anterior portion of the foot is very short." Say. SHELL ovate-conic, composed of about five * Say followed the foreign authorities in considering this to be the plural form; whereas it is the singular, the plural being ten- taculae. PALUDINA SUBPURPUREA. 29 convex whirls, of which the lines of growth are very fine and oblique: spire lengthened, with the apex scarcely obtuse: suture well marked: aperture ovate-orbicular, widest in the middle; the posterior end of the labrum is much ad- vanced upon the penultimate whirl: a few in- distinct spiral bands are sometimes visible. COLOR. The tint is difficult to define, but would be approached by a dark shade of Syme's 'brownish purple red' mixed with dark 'broccoli brow r n;' the inside being a lighter tint of the same color. GEOGRAPHICAL DISTRIBUTION. Inhabits the Wabash, and some of its branches: Mr. An- thony has received information of its occur- rence near St. Louis, and has sent me a specimen from Wisconsin. OBSERVATIONS. The tubular cylindrical organ supposed by Say to be a respiratory siphon, is probably the outlet of the viscous glands; but I am not now able to refer to Cuvier's memoir to ascertain the fact. In Paludina decisa it is strongly dotted with orange, and projects forward from the posterior angle of the aperture, at some 30 PALUDINA SUBPURPUREA. distance within the margin, being upon the right side. It will scarcely be confounded with another organ resembling the point of a tenta- cle, situated near the external base of the left tentacle. The foot is described as short in front; but although this is the case (in the genus) when the animal is in a state of repose, it is far advanced when in motion; and it is a singular fact that the rostrum of the animal is not advanced at the same time, the latter indeed, being scarcely ever visible. EXPLANATION OF PLATE 9. Figures 1 and 2 are taken from an adult specimen in the cabinet of the Academy of Natural Sciences; 3 and 4 represent half-grown shells. 31 PALUDINA INTERTEXTA, Say. PLATE 10. FIGS. 16. P. testa conica, tenui, ampullacea, diaphana: apice ob- tuso: striis transversis minutissime corrugatis: anfractibus quaternis, vel quinis: sutura valde impressa: apertura postice rotundata, intus transversim fasciata. SYNONYMS AND REFERENCES. P. INTERTEXTA, SAY. Disseminator, vol. ii. p. 244. Mrs. Say's reprint, p. 20. Amer. Conchology, pi. 30, figs. 3, 4. P. TRANSVERSA, SAY. Disseminator, vol. ii. p. 215. Mrs. Say's reprint, p. 20. DESCRIPTION. SHELL large, thin, ventricose, and slightly translucent; with about five volutions: suture deep: surface polished: lines of growth unde- viating: spiral marks and lines numerous, and very finely wrinkled: aperture large, ovate, and rounded posteriorly: opercle translucent, with the lines of accretion concentric. COLOR of the shell dark olivaceous, or brown- ish: aperture edged with black, columella white, 32 PALUDINA INTERTEXTA. inside reddish, sometimes bluish, and generally banded with reddish: opercle bright claret color. GEOGRAPHICAL DISTRIBUTION. Found abun- dantly in the neighborhood of New Orleans: South Carolina is given as the locality of specimens in the Academy's collection. OBSERVATIONS. The young shell is shorter, more transverse, the aperture proportionally wider, the peristome rarely edged with black; and the anterior por- tion of the labium is often of a bluish tinge. Say's figure was taken from a shell about the size of my figure 3, which represents a shell differing considerably from the large one figured; the two agree, however, in the minute- ly corrugated surface, and the transverse in- terior bands. The somewhat lengthened spire, and the want of an umbilic, distinguish this shell from Ampullaria, as characterized by Lamarck; al- though its approach to that genus is sufficient- ly near, to render an examination of the animal necessary, before its proper place can be per- manently determined. "It is remarkable for the numerous obsolete transverse lines; which PALUD1NA TRANSVERSA. 33 seem like equidistant corrugations of the epi- dermis ; having no effect whatever in modify- ing the calcareous surface, upon which no trace of them is exhibited." Say. I think Paludina transversa rests upon too slender grounds to be admitted as a distinct species. I give figures of the original speci- mens in the Academy's collection, and insert Say's descriptions and remarks here. PALUDINA TRANSVERSA. " Shell transverse, depressed, orbicular ; spire convex ; whorls three and a half; with nu- merous minute, slightly elevated, revolving lines ; suture not widely indented ; body whirl very convex, short ; umbilicus small ; operculum pale fulvous. " Greatest width two-fifths of an inch. Inhabits Louisiana. " We obtained two specimens in the marshes near New Orleans. It is much wider in proportion to the length than any other species I have seen, excepting in this respect even M. subglobosa, Nob., and especially P. intertexta, Nob., of which latter, in fact, I at first supposed it to be the young, in consequence of its rotundity, and the similarity of its ca- pillary lines ; but, inasmuch as the number of its whirls is nearly the same, whilst the magnitude differs so greatly, I have separated it as a different species." Say. REFERENCE TO PLATE 10. Figures 1 and 2 represent a large shell from New Orleans; a, opercle ; 3,4, are drawn from a South Carolina specimen ; 5, 6, represent Paludina transversa, Say, and 7, 8, P. sub- globosa, Say. F5 34 PALUDINA MAGNIFICA, Conrad. PLATE 11. P. testa conica, crassa, olivacea, longitudinaliter subru- gosa ; lineis duobus transversis tuberculatis ; apice truncate - erosa ; anfractibus quaternis, suturis valde impressis ; aper- tura obliqua, semicircular!, lutescente, intus transversim fasciata. SYNONYMS AND REFERENCES. P. MAGNTFICA, Conrad. New Freshwater Shells, p. 48, pi. 8, fig. 4. (May, 1834, fide Conrad.) P. BIMONILIFERA, Lea. Tr. Am. Phil. Soc., vol. 5, p. 58, pi. xix, fig. 71. (Sept., 1834, fide Conrad, UnionidaB, p. 25.) P. ANGULATA, Lea. Proceed. Am. Phil. Soc., vol. 2, p. 83 ; 1841. DESCRIPTION. SHELL ovate, conical, ventricose, apex trun- cate-eroded; whirls four, rough, with a sub- central spiral row of regular tubercles, below which upon the body whirl there is a similar but less prominent row, which is scarcely covered by the advancing growth of the pos- PALUDINA MAGNIFICA. 35 terior angle of the aperture; suture deeply impressed ; apical margin of the whirls bor- dered with a prominent subnodulous undu- lating line ; aperture wide, very oblique, and rounded anteriorly; labrum sharp, subangular, with a level margin ; opercle very thin, translucent, rectilinear upon the inner, and semicircular upon the outer side ; the margin highly colored ; the lines of growth, although indistinct, appear to be concentric. COLOR of the shell varying from yellowish green to dark olivaceous ; a dark line fre- quently covers the central row of tubercles ; the inside is generally light salmon color, banded with purple. OBSERVATIONS. The rows of tubercles are sometimes obso- lete, and replaced by subnodulous lines. Some specimens are rather ventricose, and others more slender than those figured. The young shell has only the central row of tubercles, and has the apex obtusely rounded. 36 PALUDINA MAGNIFICA. "A beautiful species when perfect, occurring in vast abundance on the masses of calcareous rock which have fallen from the strata above into the Alabama river, at Claiborne. I found it living only in such situations, and exclusively within a range of six or eight miles. In the Tombeckbe or Black Warrior rivers I never observed a specimen of it, although I searched particularly for it on the rocks at St. Stephens." Conrad. The soft parts of this form (which I have named Tulotoma) are a desideratum. The animal may be found to have dark colors in lines, and a small foot. The following Alabama species are charac- terized in Yol. 2 of the Proceedings of the American Philosophical Society : P. TROOSTIANA, Lea, p. 34, 1841. P. COOSAENSIS, Lea, p. 83, 1841. P. CYCLOSTOMAFORMIS, Lea, p. 83, 1841. P. INCRASSATA, Lea, p. 243, 1842. P. COARCTATA, Lea, p. 243, 1842. Q> P. DECISA, say. i Helen E.Lacwson dclct o.ol. ^W P SUBCARINATA, Say. Ifisa Helen E.Lawson del et col. Plate S rc vJL 5 INTEGRA, Say- Plate 4 /= PONDEROSA, Plate 5. I'laU- 0. I . Lin. I'latc 7. 1 2. /> GEORGIANS, Lea. 3_4. P BENGALEE'S IS, Ls P. CARINATA, Valen. />. SUBPURPUREA, Say. Plate ID. 1_6 I'. INTERTEXTA, Say. 7_8 P. SIBGLOBOSA, Say. P MAGNIFICA. Conrad GENUS AMPULLARIA, Lamarck. PLATE 1. Testa globosa, ventricosa, labio non calloso; apertura Integra,' marginibus connexis; labro acuto, non reflexo; operculum corneum. SYNONYMS AND REFERENCES. HELIX, LIN. NERITA, MULLER. BULIMUS, BRUG. flMPULLARiA, LAM. An. sans vert., vol. viii. p. 527. GUILDING. Zool. Journ., iii. 538, pi. supp. 27, figs. 7, 8. DESCRIPTION. ANIMAL globular, spiral; head bisected ante- riorly, each half lengthened into a short taper- ing labial palpus, having the sense of touch highly developed: "mouth terminal, circular, expanding and contracting in every direction like the opening of a purse; within, furnished with two semicircular jaws moving laterally, 6 1 AMPULLARIA. and meeting on their straight edges:"* two very long and slender tentacles arise from the base of the head, and are provided with ocu- liferous peduncles at their external base: "ovi- parous, sexes distinct, the female being much larger than the male: mantle simple, except that the upper left wing is extended so as to admit of being rolled up into a tube occasionally:")"" foot large, thin, truncated in front, with the sides parallel, or converging towards the pos- terior extremity, which is rounded, and bears the opercle. SHELL globular, ventricose, generally umbili- cated, and covered with a periostraca; aperture oval, spire short, body whirl much the largest. HABITS. A. depressa is found at Hopeton, a swamp plantation on the banks of the Alata- maha river in Georgia, U. S., about fifteen miles from the sea; moving along the bottom and sides of muddy ditches, in stagnant water, and sinks by expelling the air which has been * J. H. Couper, in letters. f Ib. Guilding describes another and shorter siphon upon the right side. AMPULLARIA. 3 taken in by the siphon. This organ has great extensibility, and is frequently protruded above the water to take in air. Whilst it is passing through the water the extremity is closed, and in its passage bubbles are frequently expelled. The palpi are constantly used as tactual organs, and the tentacles also to some extent. The food of these animals is vegetable, and the cultivated lettuce was eagerly devoured by A. depressa and an exotic species. The latter, when eating anything which was long and slender, would commence at one end and retain its hold until the whole were swallowed. If the piece were too thin to supply it fast enough, the animal would double it about the middle, and thus gradually draw in double the quantity. These two species were in vessels within doors, and were most active at night, seldom exposing the body during the day. They resemble the Physada3 in gliding over the edge of the vessel in which they are kept. OBSERVATIONS. If this genus is hydropneumonobranchiate, it is not far removed from Amphibola, which forms AMPULLARIA. a passage to the Physadse. In the shell there is some affinity with Natica, especially with those species which have not a callus upon the labium, as in N. heros, Say, (Gould Invert, of Mass., fig. 163,) which, without the opercle, might deceive a practised conchologist. For my ability to give the history of this genus I am indebted to the kindness of J. Hamilton Couper, Esq,, who has sent me an extensive series of specimens, including several living ones, with notes on their habits. He in- forms me that the species is most active in May. AMPULLARIA DEPRESSA, Say. PLATES 1, 2. A. testa subventricosa, umbilicata, laevi, olivaceo-viridi, fasciis olivaceis cincta: anfractibus 5, sutura impressa, spiral subdepressa: apertura rufescente, fasciis obscuris: operculum tenue, corneum. SYNONYMS AND REFERENCES. A. DEPRESSA, SAY. Long's 2nd Exped., vol. ii. p. 264. A. PALUDOSA, SAY. Disseminator, Aug. 12, 1829, p. 245. Mrs. Say's reprint, p. 22. Ji. HOPETONENSIS, LEA* Trans. Am. Phil. Soc., vol. v. p. 115, pi. 19, fig. 84. DESCRIPTION. ANIMAL "with the head and tentacles yellow- ish-brown in the males, and reddish-orange in the females, and in both deeply striated and dotted wittf black." Couper. SHELL subventricose, umbilicated, composed of 5 rather smooth and polished whirls, con- spicuously marked with the lines of growth: 6 AMPULLARIA DEPRESSA. suture well marked: surface with a tendency to form flattened rounded facets in some indi- viduals: spire somewhat depressed, but differing in different individuals: labrum sharp. COLOR greenish-olive or brownish-green, with a series of 10 or 15 olivaceous bands, posterior or apical margin of the whirls more or less yellow; aperture reddish-brown, varying to pur- ple, and banded with a darker tint of the same color. GEOGRAPHICAL DISTRIBUTION. Inhabits the river St. John's, according to Say, and is con- fined to a limited tract in southeastern Georgia. HABITS. "The animal lives in the canals and ditches of the rice-fields, in which the current is very small and the bottom soft and muddy. The females are oviparous, laying 30 to 70 eggs on aquatic plants or sticks (pi. 1, fig. 2) above the line of the water: eggs one-fifth of an inch in diameter, nearly spherical, slightly pointed at one end, covered with a thin cal- careous shell, flesh-coloured when first laid, but passing to a light bluish-grey. The laying sea- son commences about the end of May, and continues during the greater part of the summer. AMPULLARIA DEPRESSA. 7 The eggs are soft when first excluded, but ac- quire the hard shell within 12 hours, from the action of the atmosphere. As the egg passes out of the ovarium, it appears to be impelled on a sheet of mucus until it reaches the point to which it is to be attached, when it is accu- rately adjusted by the mere direction of the fluid, the animal remaining inactive. As soon as the first egg has been secured to its place, another is excluded from the ovarium and slowly descends in the mucus to its place." Couper, in letters. OBSERVATIONS. Say changed his first trivial name because he supposed it to be preoccupied for a fossil spe- cies, but as this proves to be a Natica, the first name need not be relinquished.* Mr. Lea alludes to Say's species and remarks * M. Deshayes (Lam. viii. 551) thinks this species (Lam. No. 7) and the succeeding ones in the same work, belong to Natica. I would extend the observation to some of the preceding fossil species, as A. spirata, A. acuminata, and A. acuta. 8 AMPULLARIA GLOBOSA. that his own is "less globose" and "flatter on the side and superior part of the whorls." Since Mr. Lea wrote, however, the shell has been found assuming several tolerably distinct forms, as the elongated, pi. 4, fig. 4; the globose, fig. 5; and the oblique, fig. 6. This species being found beyond 31 of north latitude, may be considered as occupying the northern limit of an intertropical genus. AMPULLARIA GLOBOSA, Swainson. SYNONYMS AND REFERENCES. A. GLOBOSA, SWAINSON. Zool. Illustrations. Ji. ROTUNDATA, SAY. Disseminator, Aug. 12, 1829, p. 245. Mrs. Say's reprint, p. 21. DESCRIPTION. "SHELL remarkably globose; length and breadth equal, dark brown, but becoming oliva- ceous towards the aperture: spire but little ele- vated: suture moderately impressed: body whirl AMPULLARIA GLOBOSA. 9 a little undulated instead of being wrinkled; these undulations being very perceptible to the finger within the shell: aperture within on the margin thickened equally all round and fulvous, with a slight groove for the reception of the operculum, hardly visible but palpable: within somewhat perlaceous; a little darker on the columella: umbilicus small, narrow: operculum calcareous, deeply and concentrically rugose, so as to appear stratified; nucleus on the side towards the labium, submarginal. "Length less than one inch and four-fifths; greatest breadth, about the same. "For this interesting species, we are indebted to Captain Le Conte, of the Topographical Engineers, who informed me that he found it in St. John's river, in Florida." Say. This species, as well as "Paludina elongata, Swainson" figured in this work under the name of P. bengalensis, are both given by Say as from the river St. John's, and as they have never been heard of since as occurring there, it is probable that they were introduced acci- dentally, as they are found together at Calcutta. 10 AMPULLARIA FLAGELLATA, Say. SYNONYMS AND REFERENCES. A. FLAGELLATA, SAY. Dissem. 1829, p. 260. Mrs. Say's reprint, p. 22, New Harmony, 1840. DESCRIPTION. SHELL "subglobose, olivaceous-brown, with 15 or 16 revolving, dull reddish-brown, slender bands: spire conic, moderately elevated, acute: body whirl regularly rounded, more obviously undulated or obtusely wrinkled near the aper- ture: umbilicus free, obvious: labrum a little dilated: within reddish-brown: labium, columella, and margin of the labrum, white: operculum horny. "LENGTH over one inch and a half: greatest width one inch and two-fifths. Inhabits Mexico. "Occurs in plenty a short distance below Vera Cruz. We found them immediately be- hind the sand-hillocks of the coast, in situations which, in rainy seasons, are covered with fresh water I am unacquainted with the A. linearis, Perry, which he supposes to be a native of the coast of North America. 11 AMPULLARIA URCEUS, Muller. SYNONYMS AND REFERENCES. NERITA URCEUS, MULLER. Verm., p. 174, No. 360. /?. RUGOSA, LAM., vol. viii. p. 532. A. URCEUS, FERUSSAC. Syst. Conch., p. 68, No. 3. .#. RUGOSA, LAM. VALENC. in Humb. Rec. d'Obs. deZool. etc., vol. ii. p. 258, pi. 57, fig. 2, a, 6. OBSERVATIONS. This fine species inhabits Mexico, and ap- pears never to have been found in the Missis- sippi as Lamarck supposes. (A? INTERTEXTA, Say.) Paludina intertexta, Say, presents much the appearance of an imperforate Ampullaria. Pa- ludina ponderosa, Say, which M. Deshayes sup- poses may be an Ampullaria, is a true Paludina, as some drawings of the mollusk sent me by Mrs. Say prove. A. SEPRESSA. Sav lf:.B Hrim F Uwnon 4ai .-i cal. A. DEPRESSA. Sav MiBf K>n F. i.m >r. Iri el col GENUS VALVATA, Muller. PLATE 1. FIG. 1. Testa discoidea vel conoidea, umbilicata; anfractibus cylindraceis, cavitatem spiralem non deformantibus: aper- tura rotundata, marginibus connexis, acutis: operculurn orbiculare. SYNONYMS AND REFERENCES. HELIX. TURBO. CYCLOSTOMA. NERITA. FERUSSAC. Syst. Conch, p. 75. LAMARCK. An. sans vert., vol. viii. p. 398. SOWERBY. Genera of Shells. DESCRIPTION. ANIMAL spiral; foot of medium size, divided in front, and directed outwards on each: head long, proboscidiform and slender; mouth inferior and terminal, provided with a pair of lateral jaws and a large lingual mass: tentacles long and slender, with the eyes at their posterior base : branchiae plumose, usually exserted; a long retractile filament resembling a tentacle H 1 2 VALVATA. proceeds from the right side of the neck: anus upon the right side. SHELL conoid or subdiscoid, umbilicated: volutions cylindrical or subcylindrical; aperture circular, not modified by the penultimate whirl; closed with an orbicular opercle, whose lines of growth are concentric. EXAMPLE. V. tricarinata, Say. HABITS. Found upon the muddy bottom of quiet and not very shallow waters. The ova are deposited in detached greenish globules, each containing a number of germs. OBSERVATIONS. The shell is allied to that of the marine genus Skenea, and the body whirl is not modified by the penultimate one. In the latter character it approaches to some of the species of Amnicola, and in the absence of the opercle, they cannot be properly distinguished. The species are small in size and few in number. Six recent and two fossil species are described in Deshayes' Lamarck, all of which, except V. tricarinata, occur in Europe. The VALVATA TRICARINATA. cause of this must be the carelessness of col- lectors in distant regions, in passing over ob- jects of small size; as it is not probable that the genus is as confined in its distribution as the localities of the described species might lead us to suppose. VALVATA TRICARINATA, Say. PLATE 1. FIG. V. testa viridi, turbinata; spiral bicarinata, depressa; anfractibus 3, ultimo tricarinato. SYNONYMS AND REFERENCES. CYCLOSTOMA TRICARINATA, SAY. Nich. Encyc. (Am. ed.) art. Conch. Journ. Acad. Nat. Sci., vol. i. p. 13. Anno 1817. Subsequently VALVATA. VALVATA CARINATA, SOWEKBY. Genera of Shells. V. TRICARINATA, SAY. DESH. Lam., vol. viii. p. 507. V. TRICARINATA, SAY. GOULD. Invert, of Massachusetts, p. 225, fig. 156. ADAMS. Thompson's Hist, of Vermont, App., p. 2. 4 VALVATA TRICARINATA. DESCRIPTION. ANIMAL slightly translucent, branchial fila- ment long; eyes black and conspicuous; pos- terior extremity of the foot extending nearly to the circumference of the shell, and terminating obtusely; opercle very near the extremity of the upper surface of the foot, and visible through the substance of it from the lower side. SHELL turbinate, translucent, having rather more than 3 volutions, which are smooth and prismoidal, with the lines of growth faint: spire flattened: volutions much flattened between the carinse; body whirl tricarinate; the posterior carina revolving to the apex, and the medial one just covered by the advance of the inner margin of the aperture: base widely and deeply umbilicate, umbilic bounded by the inferior carina. Opercle thin, concave externally. COLOR greenish, or light chesnut-brown; carinse whitish, with pale corresponding lines within the shell. GEOGRAPHICAL DISTRIBUTION. Inhabits New England and the Middle States. Say found it common as far west as Council BlufF, and Dr. VALVATA TRICARINATA. 5 Richardson as far north as Methy lake, in lati- tude 57. The New England specimens are smaller than those of the Middle States. "Var. SIMPLEX, without the keels. Professors Bene- dict and Adams have found this species in Vermont; and in very many instances it is perfectly simple and cylindrical, individuals occurring with every degree of carination, showing that it is still the same species.* In this state, the large tunnel-shaped umbilicus is the best characteristic." Gould. VAR. ? BICARINATA, Lea. Proceedings Am. Phil. Soc., vol. ii. p. 83. "Testa orbiculari, superne planu- lata, bicarinata, subcrassa*, superne cornea, inferne al- bida, late umbilicatS; suturis impressis; spira; depressa; anfractibus quaternis, convexis; apertura rotunda, intus albidl Hab. Schuylkill river." Lea. Mr. Lea informs me that the soft parts pre- sent a specific distinction, notwithstanding the similarity of the shell with tricarinata ami its varieties. VAR. ? UNICARINATA, De Kay, Zool. of New York. * " Varieties occur in which the middle carina is obso- lete, or in which none are very distinct." Adams. H 2 VALVATA SINCERA. OBSERVATIONS. When the posterior margin of the aperture is anterior to the medial carina, the spire be- comes bicarinate. The animal sometimes moves along in an inverted position, with the foot applied to the surface of the water. The ova are deposited from the first day of March to the end of July, in transparent masses half a line in diameter, each containing a num- ber of germs of a bright green color, dotted with yellow. VALVATA SINCERA, Say. PLATE 1'. FIG. V. testa globoso-discoidea, tenui, virescente, late per- forata, spira subelevata, anfractibus 3 4 simplicibus. SYNONYMS AND REFERENCES. V. SINCERA, SAY. Long's 2nd Expedition, Appendix. V. SINCERA, ADAMS. App. Hist, of Vermont, p. 2. VALVATA SINCERA. DESCRIPTION. ANIMAL. Head whitish, above with a tinge of slate-colour, increasing posteriorly; mouth pale yellowish; tentacles filiform, whitish, more than 0.2 inch long; eyes minute, black and shining, situated on the upper and outer part of the posterior side of the protuberance at the base of the tentacles: margin of the branchial cavity blackish-brown; pinnatifid branchia semi- transparent, consisting of a stem, on each side of which extend at right angles filiform obtuse branches bent in zigzag, shorter towards the extremity, about 10 on each side, the whole re- sembling a feather; tentaculiform branchia rather longer than the tentacles, equally slender, and obtuse: foot whitish, swelling, and regularly rounded posteriorly, with the anterior lobes sharply angular, and the middle somewhat con- tracted. Adams, in letters. SHELL "globose-discoid, obsoletely striate, brownish-green; whorls three and a half, accu- rately rounded, rapidly enlarging to the aper- ture; suture deeply impressed; spire but little elevated; apex obtuse; umbilicus deep, about 8 VALVATA SINCERA. two-thirds as wide as the last whirl; margin of the aperture touching the penultimate whirl. Length 0.1; breadth 0.2 inch; divergence of the spire about 135." Adams. GEOGRAPHICAL DISTRIBUTION. Inhabits the Northwestern Territory and Vermont. OBSERVATIONS. "This shell is much like the var. SIMPLEX of the preceding species. The umbilicus is usually a little larger, but the most striking character- istic is the rapid enlargement of the whorls, the last being more than three times the diameter of the penultimate. The divergence of the spire is never so small as in that species, but like that, is sometimes much more than in the type of the species, even to 180." Adams. VALVATA HUMERALIS, Say. SYNONYMS AND REFERENCES. V. HUMERALIS, SAY. Disseminator, Aug. 12, 1829, p. 244. j.t j DESCRIPTION. SHELL " subglobose, depressed: spire convex, not prominent: whirls three and a half; with the shoulder depressed, plane: wrinkled across, or rather with slightly raised lines: aperture appressed to the penultimate whirl, but not in- terrupted by it: umbilicus rather large. "Greatest breadth less than one-fifth of an inch. "Inhabits Mexico. OBSERVATIONS. "Differs from V. sincera of the Northwest Territory in being more depressed and in having a shoulder or plane surface near the suture. The umbilicus is larger than that of V. pisci- nalis, Mull., and the spire more depressed; the species is also destitute of the depressed shoulder." Say. 10 VALVATA PUPOIDEA, Gould. PLATE 1. FIG. V. test^ minima, conica, elongata, anfractibus 4 5 cylindraceis, ultimo a precedente disjuncto. SYNONYMS AND REFERENCES. VALVATA PUPOIDEA, GOULD. Invert, of Mass., p. 226, fig. 155. DESCRIPTION. ANIMAL "very active; head proboscidiform, half as long as the tentacles, bi-lobed in front, dark, terminated with light; tentacles rather stout, light drab-colored, with a line of silvery dots on the upper side, over the large, black eyes; foot tongue-shaped, as long as the first whorl, dilated into two acute angles in front, light drab-color; respiratory organ occasionally protruded to half the length of a tentacle on the right side. SHELL "small, elongated-ovate, opake, ches- VALVATA PUPOIDEA. 11 nut-colored, when divested of the rough, dirty pigment which usually adheres closely to it; whorls four or five, minutely wrinkled, the pos- terior one small and flattened so as to form an obtuse apex; the others cylindrical, and so par- tially in contact as to expose about one-half of the cylinder; the last entirely disjoined from the preceding one for at least the half of a revolu- tion [in the adult]; aperture circular, lip simple and sharp; on looking at the shell from below, no umbilical opening is found; operculum horny, apex central, elements concentric. Length one- tenth, breadth three-fortieths inch." Gould. GEOGRAPHICAL DISTRIBUTION. Found in ponds in the vicinity of Boston, Massachusetts, ad- hering to submerged sticks and stones. OBSERVATIONS. In its immature state, before the body whirl is detached, this species cannot be distinguished from Amnicola, except by the opercle, and the slightly ovate aperture adds to the deceptive character of the shell. The separation of the last whirl deprives the shell of a proper umbilic. 1_4. 17 TR1CARINATA, Sa,v 6_10- K SINCERA, Sax* 11_13. F PTJPOIDEA, Goxdd Hden E. L IWSOIL iel. et col. INDEX To the genera AMNICOLA, AMPULLARIA, PALUDINA, and VALVATA. Synonyms are in italics. The part devoted to each genus is paged separately. Amnicola attenuata, . p. 22, fig. 13 cincinnatiensis, 9, f. 4 cincinnatiense, 19 decisa, . 7, f. 13 elongata (err cler.) f. 9 17 18, f. 10 10, f. 5, 6 16 10, 12 21 f. 12 24 f.7 24 f. 8 10 19, f. 11 23, f.14,15 . . . 5 . 10 12, 13, galbana, granum, . lapidaria, limosa, . lustrica, . lustrica, . nicliniana, orbiculata, pallida, . parva, . . porata, . porata, sayana, . tenuipes, Ampullaria depressa, flagellata, Slobosa, o opetonensis, ... 5 ? intertexta, . ... 11 paludosa, 5 rotundata, .... 8 rugosa, 11 urceus 11 Oyclostomacincinnatiensis,A.w.in.coiA.,l9 Nerita urceus, . . . AMPULLARIA, 11 Paludina angulata, 35 bengalensis, .... 24 bimonilifera 35 carinata, 26 carinata, 8 cincinnatiensis, AMNIC., 9 coarctata, 36 coosaensis, 36 Paludina cornea, 4 cyclostomaformis, . . 38 decisa, 4 elongata \\ Sw., .... 24 fasciata, Bowd., ... 24 genicula, 15 georgiana, 23 grana, , . AMNICOLA, 17 heterostropha, .... 4 incrassata 36 integra, 10 intertexta, 31 lapidaria, . AMNICOLA, 18 limosa, . . AMNICOLA, 10 limosa (Val.), .... 4 lineata, 17 lustrica, AMNICOLA, 10, 12, 16 magnifica, 33 multilineata, .... 24 nickliniana, . AMNICOLA, 21 obtusa, . . AMNICOLA, 24 ponderosa 13 porata, . AMNICOLA, 10, 13 subcarinata, .... 8 subpurpurea, .... 28 transversa, 31 yivipara 17 Valvata bicarinata, . "\ . . . 5 carinata, 3 humeralis, g pupoidea, lo simplex, 5 sincera, 6 transversa, 33 troostiana, 35 tricarinata s unicarinata, 6 COERECTIONS. PHYSAD.E, p. 8, 1. 9, dele more highly. 22, 1. 5.J., read negroes. 26, 1. 14., for 2 read a, and for 3 read 2. LIMNEA, p. 4. The tentacles are very sensi- tive, as indicated by the fact that if a drop of ink or other colored acrid fluid be placed near them, they will be suddenly withdrawn, and the course of the animal altered. The use of a colored liquid enables one to know the mo- ment of its contact with the tentacle. LIMNEA, p. 33, 41, 49, for signature K read J (5, 6, 7). PALUDINA, p. 22, 1. 4, 6.J., read urceus. CONTENTS. This work contains the eight signatures I, J, K, L, and E, F, G, H, each set of four restricted to one of the two great groups of air-breathing and water-breathing genera. These may be bound separately, although the book is intended to form one volume. The indications of synonymy on the covers being founded upon short descriptions, and the title on the numbers from 1 to 5, as published, are cancelled as temporary, and the matter of an unpublished specimen number, and of most of the covers, is superseded, as the remainder must be in a few years. In the meantime, those who wish to preserve the indications of new species catalogued below, can preserve the last leaf of the covers of numbers 1, 2, 3, 4, and 7. Title of 1842. Dedication. Preface. Signa- ture 1 1 5, and 5 plates of PHYSA. No. 6, January, 1843. Sig. Jl 7, and 15 plates of LIMNEA. (J5, 6, 7, are marked K5, 6, 7, in error.) No. 3, pp. 1 16, pi. 1 5, July, 1841, with short charac- ters on the cover, of Paludina rufa, Anculosa fusca, Ancy- lus nuttalliij A. diaphanus, Lim. ferruginea, Physa integra, 42 CONTENTS. Melania varicosa (Ward), Bulimus vermetus (Ant.), Mel. iuflata, M. curta, Physa concolor, Anculosa affinis. No. 4, pp. IT 32, pi. 610, Jan., 1842, with short charac- ters on the cover, of Anculosa crassa, Melania aequalis, un- cialis, symmetrica, bellacrenata, gracilisvelpulchella(Ant.), approxima, intersita, Limnea vitrea, Physa globosa, Amni- cola attenuata, pallida, galbana, sayana. Pal. carinata (Val.) is changed to multicarinata, and carinata (Sw.) to unicarinata. Sig. Kl 4, and 4 plates of PLANORBIS. No. 7, pp. 1 32, pi. 1 4, Jan. 1844, including Ancylus. The cover has characters of Amnicola tenuipes (Couper), and Melania substricta. Sig. LI 2, and 1 plate. INDEX, commenc- ing with the word Acella. Title of 1845. Sig. El 3, and 1 plate of AMNICOLA. No. 8, June, 1845, including Ampullaria and Valvata. Sig. Fl 5, and 11 plates of PALUDINA. No. 1, pp. 1 16, pi. 1 5, July, 1840, with characters on the cover of Anculosa littorina, Potamis californica, Cyclas elevata, Clepsina scabra, Cercaria hyalocauda. No. 2, pp. 17 32, pi. 610, Jan., 1841, with characters on the cover of Mel. rufula, costifera, Physa fontana, oscu- lans, Ancylus parallelus, and Angitreuia proposed for Me- lania armigera. CONTENTS. 43 Sig. Gl 2, and 2 plates of AMTULLARIA. Si g . HI 3, and 1 plate of VALVATA. INDEX to Amnicola, &c. ERRATA. CONTENTS. FINIS. Opercles subspiral: inhabit rapid streams: oviparous. Peristome continuous: foot large, oblong. f the Waterbreathing Limniades. r Peristome not entire, foot oval. i 5 Q C^ *-* ^ S 1, 1 'i j 3 S _ 31 ~ co I? fac 5 q .S = 13 11 1 i IS* II posed, foot emarginate; inhabits Sub-typical. \ Inhabit quiet waters: oper- cles mostly concentric. J > >> 1^ 1 'S - S CD K "^ C C 2 fe | ^ 13 2 1 ; | *2 ! 1 i C cd <+H .2 ^ a ^r |1| I ^ g 'i " co 3 H o o CO >>^ ^3 & Characters oot of medium cs _c c co 2 hD c anterior note! CO fl o "C3 a> C3 C3 iter, attached t C3 CD C O CD I CO o> in c o co" A cd ^ 'o 11, rostrum ver Id cd o c CD > cd o cd .S Id S S R CD J ^ lo cd .1 hn c 'o Cd s 'cd a cd PH "cd fe 1 a> -S CO cf 1 C cd ^ fco 1 2 o s 1 'S CO c o I .2 '3 'a CO b & b CO inning | 1 1 "So 2 bJO Id CO ^ 1 -a ^ "o o k "cu M 1 C 1 11 'S M ^ 1/i < t-H t i 1 LANIA. LANOPS CULOSA, NICOLA. LUDINA. PULLAR LVATA. H H 'Z Sj NATURAL RESOURCE LIBRARY 2101 Valley Life Sciences Bldg. 642-2531 LOAN PERIOD ALL BOOKS MAY BE RECALLED AFTER 7 DAYS. DUE AS STAMPED BELOW. \ Jr' FORM NO. DD8 UNIVERSITY OF CALIFORNIA, BERKELEY 24M 4-00 Berkeley, California 94720-6500 _. /p^"~i \ \^ ^ \ y U.C.BERKELEY LIBRARIES