150 FISHES OF MASSACHUSETTS. 



The Anal commences in front of the posterior angle of the 

 operculum, and terminates on the same plane with the dorsal. 



The Caudal fin is one third longer than the width of the base. 

 The rays of each fin are covered by scales ; and those project- 

 ing backwards, present a very beautiful serrated appearance, 

 more strongly marked on the right side of the body, the scales 

 of the fins on the left side being colorless. The interstices 

 between the fin rays, are black. 



The fin rays are : D. 52 ; Y. 4 ; A. 40 ; C. 16. 



Although Mitchell's description is generally correct, and 

 might have been copied, had I not determined to describe each 

 species, so far as possible, from recent specimens, one point re- 

 quires correction. He says, "it is soft and mucous, without a 

 spire or prickle about him." Whoever will carefully examine 

 this species, will observe imbedded in the surrounding flesh, a 

 strong compressed spine two thirds of a line in length, situated 

 directly in front of the upper eye, and in a line with it, just 

 back of the commencement of the dorsal fin, almost entirely 

 concealed. This evidently escaped the notice of Mitchell, as 

 in other respects, he is clear and satisfactory. 



I cannot speak so well of his figure, for the dorsal fin, in- 

 stead of commencing in front of the eyes, is represented as 

 taking its origin some distance back of them ; the anal is 

 figured as beginning too far back ; and the base of the tail 

 appears as if distorted. 



Family HI. 

 DISCOBOLI. 



Ctclopterus, — subgenus. 



LuMPus. Cuv. 



Generic characters. Head and body deep, thick, and short ; 

 hack with an elevated ridge, the investing skin enclosing sim- 

 ple rays ; pectoral fins uniting under the throat, and with the 

 ventrals forming a single disk. 



