III. COTTOIDS OF NORTH AMERICA. 51 



Preserved specimens exist in the cabinet of the Boston Society of Natural History; 

 in the State Museum, at Albany ; and at the Smithsonian Institution. 



VIII. COTTUS VISCOSUS, HALD. = 

 PLATE II. Figs. 1 and 2. 



Syn. Coitus viscosus, HALD. Suppl. to a Monogr. of Limn., &c., 1840, p. 3. GIRARD, Proc. Amer. Assoc. 

 Adv. Sc. II., 1850, p. 411 j and, Proc. Boat. Soc. Nat. Hist. III., 1850, p. 189. 



In 1840, this species was announced to the scientific world rather than described. 

 The author having no means of establishing direct comparisons, could not draw an 

 accurate distinctive diagnosis. He knew not Mr. Heckel's C. gracilis, and had only 

 before him an incomplete description of C. gobio, from Europe. 



The specimen figured, is not quite four inches long. Since the latter has been 

 drawn, we have seen another, measuring nearly four inches and a half. 



The general form is sub- cylindrical, of rather stout appearance. The width, near 

 the head, is greater than the depth, and sometimes both of these dimensions are 

 equal. The greatest depth under the first dorsal, is comprised five times and a half 

 in the entire length, and the least depth a little more than fifteen times. The head 

 forms the two-ninths of the length of the fish. The occipital region is depressed, 

 but flat; the nose convex, and the snout obtuse. The mouth is very little cleft, and 

 its angles do not extend farther back than the anterior rim of the eye. The lips 

 are very fleshy. The eyes themselves are of medium size, and circular in form ; their 

 diameter is contained five times in the length of the head. The tubular nostrils 

 are nearer the eyes than the extremity of the jaws. The preopercular spine is stout 

 and prominent, acute, directed obliquely upwards. In some cases there exists a 

 second, very small, slender, acute spine, immediately under the base of the first, 

 having its point directed vertically downwards. That on the inferior angle of the 

 subopercular is very conspicuous, acute, directed as usual downwards and forwards. 

 The gill openings are separated, below, by an isthmus of three-eighths of an inch. 



The anterior margin of the first dorsal is distant one inch and a quarter from 

 the extremity of the snout. It is rather low, uniformly arched, and composed of 

 eight rays, the third, fourth, and fifth, nearly equal, and longest. The mem- 

 brane between that fin and the second dorsal is quite low. The second dorsal is 

 convex like the first, containing seventeen undivided rays on a base of one and 

 an eighth of an inch, twice and a half as long as the base of the anterior fin. The 

 origin of the anal is under the fourth ray of the second dorsal and is more convex 

 than the latter. It is composed of twelve undivided rays, the last, as in many 

 instances, double, opposite to the fourteenth of the second dorsal. The longest rays 

 of both second dorsal and anal, are of equal length, but the membrane of the 

 latter fin is more deeply notched, so as to make it appear shorter. The caudal is 

 rounded posteriorly, and forms two-elevenths of the entire length. It is composed 

 of eleven well developed rays, with four short ones above and three below. The 

 nine middle ones are bifurcated on the last two-thirds of their length, and each 

 branch again subdivided near the tip without solution of continuity ; this latter 



