GEN. CRENILABRUS. THE ROCK-COCK. 305 



Mr. Couch had designated it Crenilahrus microsto- 

 ma^ a very appropriate specific appellation ; for the 

 smallness of its mouth immediately distinguishes it 

 from its congeners, and M. Valenciennes followed in 

 his wake, naming it Acantholahrus microstoma ; and 

 yet, after all, it turns out to be a fish w^hich has been 

 long known to the Naturalists of more northern 

 regions. M. M. Fries and Ekstrom have given 

 a coloured representation in the second part of their 

 Fishes of Scandinavia, which, when compared with 

 the dra^^^ng made by the draughtsman of the Sur- 

 vey, and published by Mr. Thompson, leaves no 

 doubt of the fishes being the same, and of their 

 identity with the Lahrus exoletus of Linn^us. It is 

 a small fish, seldom exceeding six inches in length ; 

 and is known upon the coasts of Norway, Sweden, 

 and Denmark, and, according to Fabricius, as far 

 north as Greenland ; where, however, it is said to 

 be rare. Its most prominent characteristics are, 

 that the body is rather deep, the mouth small, the 

 teeth few in number ; the scales very large, those 

 on the body concealing the base of the dorsal and 

 anal fins, although there are none upon the fins 

 themselves; the anal fin has five or six spinous 

 rays ; no blackish spots occur upon the body or fins : 

 there is a slight elevation above the eye in the line 

 of the frontile profile. The colour of the head and 

 body is dark brown on the upper parts, passing into 

 pale wood-brown beneath, and on the sides and ab- 

 domen ; the colour of the dorsal, caudal, and anal 

 fins is dark brown; of the pectorals and "ventral, 



