HISTOEY OF THE FISHES OF MASSACHUSETTS. 405 



lines in width, at the pectorals it grows wider, is widest beneath them, and becomes 

 gradually smaller as it approaches the posterior extremity of the fish. The first ray of 

 the dorsal fin is margined with white. The pectorals are the color of the body. The 

 anal fin is dark-colored, edged with white. The upper and lower extremities of the 

 caudal fin are white. 



Description. Body cylindrical, elongated. The greatest depth of the body, exclu- 

 sive of the fins, is equal to one tenth its length. The length of the head, from 

 the tip of the lower jaw to the posterior angle of the operculum, is equal to about 

 one seventh the entire length of the fish ; the depth of the head at the posterior 

 portion is equal to half of its length ; its width over the same portion is equal 

 to one third of its length. The top of the head is flattened ; the body between 

 the disk and the dorsal fin is nearly circular; back of the dorsal fin it is some- 

 what compressed. Upon the top of the head is an adhesive disk, about one fifth the 

 length of the body, at its anterior extremity equal in width to about one third the 

 length of the head ; the widest part of the posterior extremity is slightly greater. This 

 disk extends from the tip of the upper jaw to the middle of the pectorals ; it has 

 twenty-one light-colored transverse plates, divided by a longitudinal median fleshy 

 line ; the entire disk is margined by a fleshy border from one to four lines wide. The 

 eyes are situated half-way between the tip of the lower jaw and the extremity of 

 the operculum ; they are circular, and between three and four lines in diameter. The 

 nostrils are double, with fleshy appendages. The jaws are crowded with numerous 

 small, card-like teeth. Teeth also are observed in the throat and upon the palatine 

 bones. The lower jaw terminates in a point in advance of the upper. 



The dorsal fin arises just anterior to the middle of the body. It is rather more 

 than one third the length of the fish. It is of a dark slate color; the tips of the 

 anterior rays are edged with white. 



The pectorals commence on a line with the posterior fifth of the disk ; their depth 

 to their length is as one to three. 



The ventrals are situated just posterior to the pectorals ; their depth is equal to 

 one sixth their length. 



The anal fin arises directly opposite, and terminates upon the same plane as the 

 dorsal. Its anterior rays are higher than those of that fin. The anus is half an 

 inch in front of this fin. 



The caudal fin is nearly even at its extremity. 



The fin rays are as follows: — D. 29. P. 18. V. 5. A. 30. C. 18. 



Length, twenty inches. 



YOL, viii. 63 



