214 B L A C K G O B Y. Class IV. 



bitant of rivers, which lad feems to have been our 

 common gudgeon. 

 PtscRip. 'p^jg fpecies grows to the length of fix inches : 

 the body is foft, flippery, and of a {lender form : 

 the head is rather large •, the cheeks inflated ; the 

 teeth fmall, and difpofed in two rows : from the 

 head to the firft dorfal fin is a fmall fulcus. 



The firft dorfal fin confifts of fix rays •, the fe- 

 cond of fourteen ; the pectoral fins of fixteen or 

 feventeen, clofely fet together, and the middlemoft 

 the longed -, the others on each fide gradually 

 fhorter. 



The ventral fins coalefce and form a fort of 

 funnel, by which thefe fifh affix themfelves im- 

 moveably to the rocks, for which reafon they are 

 called Rock-fijh. 



The tail is rounded at the end. 



The color is brown, or deep olive, mixed with 

 dark ftreaks, and fpotted with black : the dorfal 

 and anal fins are of a pale blue, the rays marked 

 with minute black fpots. 



K<pvul 



