183 both at the water’s edge and on the summits of the most elevated hills. Those in the bays, as at Green Bay, were nearly all situ- ated near the low water mark, and may doubtless have been drifted in by the floating ice which makes its appearance on the coast every spring; but a different explanation must be given to account for those on the elevated rocks and hills. Nearly all the protruding rocks are rounded and the marks known as “Drift marks,” “Diluvial scratches,” and “ Glacier marks,” existed in great abundance. The smooth and rounded rocks are especially observable at Bras d’Or. They are all rounded on the northern side. Prof. Agassiz remarked that in Cambridge, on the road to Mount Auburn, there may be seen at the present time, in a recently opened gravel-pit, an instance of the two kinds of drift, one above the other. The upper one is of marine and the lower of glacial origin. The former is made up of different materials, distinctly stratified, and exhibits marks of tidal action, but contains no boulders. The lower one consists of small and large pebbles, more or less scratched, irregularly scattered through a bed of mud. Dr. Cabot stated, that at Deer Island, in Boston Harbor, a similar drift deposit may be seen. Mr. Girard read a paper on the genus Coitus. ON THE GENUS COTTUS Auct. There are in the genus Cottus, as it has hitherto been admit- ted, two groups of species always very easily distinguished from each other at first sight; the head of the one is smooth or nearly so ; that of the other is tuberculous, or armed with spines ; the former inhabits fresh water, the latter salt or brackish water at the mouths of rivers. These two groups are generically distinct both by external characters and anatomical structure. It remains only to decide which should retain the name of Cottus, and to which it will be necessary to give a new name. The most simple way to settle this question, will be to go back to the origin of the genus Cottus and follow its history. 184 Artedi established it in 1738 with the following characters : — Gill-membrane containing six distinct bony rays; head larger than the body, depressed and acute. Two dorsal fins ; the an- terior one composed of flexible spines. Ventral fins small, hav- ing only four soft rays. Skin scaleless.* He places in the first rank the fresh water species having two spines on the head, of which C. gobio is the type, being the only one known at that time. Next the species with more spines on the head, including not only the salt water species having a smooth skin instead of scales, but two others which have since become, one the type of the genus Aspidophorus, the other, the type of the genus Callionymus. Artedi himself went thus beyond the limits of his genus by placing in it the two last species, as their body is covered with scales. Linnaeus f alters Artedi’s genus by giving as the only charac- ter for it, “ a spiny head broader than the body." Linnaeus went further ; he transposes the species and places at the head C. cataphractus, the type of the genus Aspidophorus, of later date, and which Artedi placed at the end of the genus Cottus. His third species belongs now to the genus Batrachus, and the fourth to the genus Platycephalus. The C. gobio is the last. FabriciusJ followed the example of Linnaeus. Cuvier§ 'i£calls$lre primitive type of the genus gobio, from the fresh waters of Europe, in which have been since dis- tinguished several species which were formerly confounded. Cuvier, following Artedi, describes first the fresh water, and next the salt water species. But when the celebrated ichthy- ologist wrote the history of this genus, he did not find it necessary to separate generically these two groups, although he had already pointed out their principal differences. There were only two fresh water species known, and that imperfectly. Now that their number is considerably increased, and the study of them has become somewhat more difficult, it seems proper to subdivide the genus Cottus of the different authors in the follow- ing manner : — * Genera Piscium. t Systema Naturae, ed. xii. $ Fauna Grcenlandica, 1780, 8. § Histoire Naturelle des Poissons, vol. iv. 1829, pp. 142, 150. 185 I propose the name of Acanthocottus, for the marine species, which are generally of a larger size than those found in fresh water.* They are characterized by having spines upon each of the opercular bones. The preoperculum itself has several always strongly developed. The surface of the head, and also often the circumference of the orbits, are either armed with spines, or else they are serrated or notched in different ways. The nasal bones are also in most of the species surmounted by a spine or ridge. The head itself is rather higher than broad ; sometimes much deformed, with proportionally very large eyes, and a deep occipital depression. The mouth is always more deeply cleft than in the fresh water species, but the denti- tion, as a whole, is nearly the same. Nostrils double, distant from each other, tubular, the anterior being much larger, the posterior close to the orbit. The body is scaleless ; the back is often arched, and the first dorsal fin almost as high as the second. Some species have three, others four, soft rays to the ventral fins. The lateral line runs uninterrupted from the head to the base of the caudal fin. The American species of this genus are the following: — Acanthocottus Grcenlandicus Grd. — Cottus Gramlandicus Cirv. & Val. Hist. Nat. Poiss. iv. 1829, p. 185. — Rich. Faun. Bor. Amer. hi. 1836, p. 46, and Add. p. 297, PI. 95, fig. 2.—Storer Rep. 1839, p. 16. — DeKay, New York Fauna, 1842, p. 54, fig. 10. — Storer, Synops. 1846, p. 53. Cottus quadricornis Sabine, App. to Parry’s First Voy. 1821. Cottus scorpius Fabr. Faun. Groenl. 1780, p. 456. Cottus variabilis Ayres, Proc. Bost. Soc. Nat. Hist. i. 1842, p. 68, and Bost. Journ. of Nat. Hist. iv. 1843, p. 259. (Young) — Greenland; Cuvier and Valen- ciennes.— Davis Strait; Richardson.—Maine and Massa- chusetts ; Storer. — Connecticut; Ayres. — Hellgate (N. Y.) ; DeKay. Acanthocottus scorpioides Grd. — Cottus scorpioides Fabr. Faun. Groenl. 1780, p. 157. — Cuv. & Val. Hist. Nat. Poiss. iv. 1829, p. 187. — Richards. Faun. Bor. Amer. * With the exception of C. polaris; but the specimens which have been ob- served may not have been full-grown. 186 hi. 1836, p. 47. — Storer, Synops. 1846, p. 54. Green- land ; O. Fabricius. Acanthocottus polaris Grd.— Coitus polaris Sabine, App. to Parry’s First Voy. 1821, p. ccxm. & J. C. Ross, App. to Parry’s Third Voy. 1826, liii. — Rich. Faun. Bor. Amer. iii. 1836. p. 43. — Storer, Synops. 1846, p. 55.— Peninsula of Boothia (Ross); Sabine. — Lat. 75°, Shores of North Georgia ; Richardson. Acanthocottus polyacanthocephalus Grd. — Coitus polya- cantlwceplialus Pall. Zoogr. Ross. Asiat. 1811, p. 133, PI. 23. — Cuv. & Val. Hist. Nat. Poiss. iv. 1829, p. 176. — Richards. Faun. Bor. Amer. iii. 1836, p. 48. — Storer, Synops. 1846, p. 55. — Off Cape St. Elias (Billings) 60° lat. N. ; Richardson, Valenciennes. Acanthocottus psittiliger Grd. — Coitus psiltiliger Pall. Zoogr. Ross. Asiat. iii. 1811, p. 143, PI. 20, fig. 3 and 4.— Cuv. & Val. Plist. Nat. Poiss. iv. 1829, p. 193.—Rich. Faun. Bor. Amer. iii. 1836, p. 48. — Storer, Synops. 1846, p. 54. — Unalaska and Harbor of Avatcha ; Cu- vier and Valenciennes. — Coast of Kamtschatka ; Rich- ardson. Acanthocottus hexacornis Grd.—Coitus hexacornis Richards. Frank. Journ. 1823, p. 726, & Faun. Bor. Amer. in. 1836, p. 44. — Storer, Synops. 1846, p. 55. — Mouth of Tree River, lat. 67° 12" N.; Richardson. Acanthocottus porosus Grd. — Cottus porosus Cuv. & Val. w//. o/ Hist. Nat. Poiss. 1836V, p. 498. — Rich. Faun. Bor. Amer. in. 1836, p. 47. — Storer, Synops. 1846, p. 56. Baffin’s Bay ; Richardson. Acanthocottus aineus Grd. — Cottus ccneus Mitch. Tr. Lit. & Philos. Soc. New York, i. 1815, p. 380. — Cuv. & Val. Hist. Nat. Poiss. iv. 1829, p. 189. — Storer, Rep. 1839, p. 20. — DeKay, New-York Fauna, 1842, p. 52, fig. 19. — Storer, Synops. 1846, p. 54.—New York ; Mitchill, DeKay. — Massachusetts ; Storer. Acanthocottus Mitchilli Grd.— Cottus Mitchilli Cuv. & Val. Hist. Nat. Poiss. iv. 1829, p. 188. — DeKay, New York Faun. 1842, p. 53, fig. 46. — Storer, Synops. 1846, p. 56. Cottus scorpio Mitch. Tr. Lit. & Philos. Soc. New York, i. 1815, p. 381. — New York ; Mitchill, DeKay. 187 Acanthocottus Virginianus Grd. — Scorpius Virginianus Willugb. Hist. pise. App. 1685, p. 25, PL 10, fig. 15. Cottus scorpius Schcepff, Beobach. &c. vm. 1788, p. 145. Cotlus oclodecemspinosus Mitch. Tr. Lit. & Philos. Soc. New York, i. 1815, p. 380. — Cuv. & Val. Hist. Nat. Poiss. iv. 1829, p. 181. Griff. Cuv. x. 1834, PI. 43, fig. 4 .— Rich.- Faun. Bor. Amer. m. 1836, p. 46.— Coitus Virginia- nus Storer, Rep. 1839, p. 18. — DeKay, New York Faun. 1842, p. 51, fig. 13. — Storer, Synops. 1846, p. 54. Coast of Virginia; Willugby.—New-York ; Mitchill, DeKay. — Newfoundland ; Richardson. I have not been able to make the comparative study of the species of this genus as complete as I could desire, not having had sufficient materials at my disposal. I have nevertheless ascertained one fact which I think will not be without interest in the history of the species — namely, that the C. variabilis Ayres, is the young of the A. Grcenlandicus. This fact shows the im- portance of studying these fishes throughout their different stages of growth if we wish to arrive at a complete knowledge of the species. The C. variabilis, which was at first believed to be restricted to the shores of Connecticut, has been since found at Chelsea, Massachusetts, by Mr. W. O. Ayres himself; and Mr. Horatio R. Storer brought it the last summer from the shores of Labra- dor, together with young A. Virginianus. The geographical distribution of this species follows therefore that of A. Grccnland- icus with which I have identified it by the study of its Zoologi- cal characters. The examination of the young Acanthocotti has also apprised me of the fact that the spines of the preoperculum vary within certain limits. Thus I have noticed some individuals which had three spines on one side and two only on the other. It is already known that one of the spines may be occasionally bifurcated, but in the instance above mentioned the third spine was not the result of a division ; their respective position left no doubt with regard to this point. It would be very interesting to compare authentic specimens of the C. scorpius, Fabr. (A. Grcenlandicus) with the species of the same name of the coast of New England, Newfoundland, 188 and Labrador. I cannot help thinking that there are two species confounded under the name of gramlandicus, the comparative study of which will alone enable us to determine. Should they prove to he distinct, the name of variabilis could be restored for the species of the western coast of the Atlantic. Next to the Acanthocottus must be placed the genus Tra- chidermis Heckel. characterized by a rough skin, and teeth on the palatine bones ; as for the rest, similar to the foregoing in its general appearance. The body is perhaps more fusiform and the armature of the head and of the opercular apparatus less developed. The head is very depressed, and the mouth deeply cleft. But one species of this genus is known, the T. fasciatus Heck.* from the Philippine Islands. It is a fish of a small size. I shall preserve the name of Cottus Artedi, for the fresh water species, having but one small spine at the angle of the preo- perculum, and sometimes another still smaller, always hidden under the skin and perceptible to the touch only, at the lower margin of the suboperculum. The head itself is very depressed, more or less truncated in front, generally broader than high, but always very uniform, being scarcely detached from the body unless by its more considerable breadth. mouth is less deeply cleft than in the Acanthocotti. Like the latter they have teeth on the intermaxillaries, on the lower maxillaries and on the front of the vomer. Sometimes at a younger age, the palatine, bones are rough, indicating rudimentary teeth; these bones become smooth in the adult. Nostrils double, as in the Acanthocotti. The body is also smooth, scaleless, and taper- ing to the tail. The first dorsal is always less high than the sec- ond ; the back is but little arched and projects little or not at all above the nape. The ventral fins have three soft rays in some species and four in some others. The lateral line is sometimes interrupted, as in the greater number of American species,! sometimes continuous throughout the total length of the body, as is the case with all the species of the old world. The generic name of Uranidea has been given to a species of the genus Cottus by a mistake of its author. Nevertheless, if the * Annalen des Wiener Museum, Vol. ii. 1837, p. 159, PI. 9, figs. 1 and 2. t Mr. Heckel has made of it one of the characters of his C. gracilis, the single American species which he saw. 189 principles of nomenclature had transferred the name of Cottus to the marine species, I should not have created a new one for the fresh water species. I should have adopted the genus Uranidea although unfortunately chosen, knowing how small a number of names have a true etymological signification, and how many are arbitrarily applied. There are in North America : — Cottus cognatus Richards. Faun. Bor. Amer. hi. 1836, p.40. Great Bear Lake ; Sir John Richardson. Cottus Richardsonii Agass. Lake Superior, 1850, p. 300. Northern shores of Lake Superior ; Prof. Agassiz. Cottus Bairdii Grd. — Cottus gobio Kirtl. Bost. Journ. Nat. Hist. v. 1847, p. 342. — Body subcylindrical, short, mouth comparatively large. — Pennsylvania, tributaries of the Ohio ; Prof. Baird. — Mahoning River ; J. P. Kirtland. Cottus meridionalis Grd. Resembles the former, but the tail tapers away more suddenly. The mouth is also a little larger. — James River ; Prof. Baird. Cottus gracilis Pleck. Ann. des Wien. Mus. ii. 1837, p. 148. — Uranidea quiescens DeKay, New York Fauna, 1842, p. 61, PI. v. fig. 14. — Cottus gobio Ayres, Bost. Journ. Nat. Hist. v. 1845, p. 121, PI. xi.—New York ; IJeckel, DeKay. — Manchester, Connecticut, W. O. Ayres. Cottus viscosus Hald. Suppl. to a Monogr. of Limn. &c. 1840, p. 3. Eastern Pennsylvania ; Professors Plaldeman and Baird. Cottus boleoides Grd. Remarkable for its slender body and its largely developed fins. Windsor, Vt.; Ed. C. Cabot, Dr. Storer. Cottus Franklinii Agass. Lake Superior, 1850, p. 303. Eastern and Southern shores of Lake Superior; Prof. Agassiz. Cottus gobioides Grd. Body thick and short; mouth very large. — Burlington, Yt. ; Rev. Z. Thompson, Dr. D. H. Storer. Cottus Fabricii Grd. — Cottus gobio Fabr. Faun. Grcenl. 1780, p. 159. — Greenland ; O. Fabricius. There remains one species which cannot be placed in any of the preceding genera, it is the C. asper Rich, from Columbia 190 River.* Mr. Heckelf had placed it in his genus Trachidermis, where I do not believe that it can remain, notwithstanding its rough skin and its teeth on the palatine bones. Dr. Richardson has felt the necessity of withdrawing it from the genus Cottus. In the “Fauna Boreali Americana,” he thought the genus Hemilepidotus might perhaps receive it, but he himself has acknowledged since, that its place was not there, and when establishing the genus J for some species of the China seas, he proposed to associate with them the C. asper. Not having at my disposal sufficient materials to satisfy myself upon this subject I shall reconsider it in a monograph of the species of Cottus of North America, which I am now engaged in preparing. Dr. Gould presented, in the name of Capt. Joseph P. Couthouy, a specimen of Volcanic Ammonia, brought home from the United States Exploring Expedition. Rajinder Datt of Calcutta was chosen a Corresponding member of the Society. November 7, 1849. The President in the Chair. Present, twenty-nine members. Present, by invitation, M. H. Perley, Esq. of New Brunswick. Prof. Agassiz said that he had been for some time en- gaged in the study of the Worms of the coast of Massachu- setts, and he had obtained some very interesting results. He had found that in many of the Annelids which, at an early stage of their development are furnished with a pair of eyes to each ring, these organs gradually disappear, so that at maturity * Faun. Bor. Amer. hi. 1836, p. 295, PI. 95, fig. 1. t Ann. d. Wien. Mus. n. 1837, p. 162. \ Ichthyology of the “ Sulphur.”