THE FISHES OF NEW JERSEY. 389 



It is known from our coast by Dr. Abbott's record. Reaching 

 a length of 15 inches and found attached to large-sized sharks. 

 I ha.ve no New Jersey examples. 



Bcheneis remora Abbott, Geol. N. J., 1868, p. 814. 



Sub-Order HETEROSOMATA. 



The Flat Fishes. 



A large group of fishes which are remarkable for their twisted 

 cranium, the eyes and color on one side in the adult, while in the 

 very young the two sides of the body are alike. 



Key to the families. 



a. Preopercular margin more or less distinct, not hidden by skin and scales 

 of head ; eyes large, well separated ; mouth moderate or large ; teeth 

 present. pIvEuronectid^ 



aa. Preopercular margin adnate, hidden by skin and scales of head ; eyes 

 small, close together ; mouth very small, much twisted ; teeth rudimentary 

 or wanting. soleid^ 



Family PLEURONECTID^. 



The Flounders. 



Body strongly compressed, oval, or elliptical in outline. Head 

 unsymmetrical, cranium twisted. Both eyes on same side of body, 

 which is horizontal in life, eyed side uppermost, and blind side 

 lowermost and usually plain. In very young, bones of head 

 symmetrical, i eye on each side, body vertical in water, mostly 

 cranium becomes twisted, bringing eye over with it, eyes 

 large, well separated. Mouth small or large, dentition various, 

 and teeth always present. Premaxillaries protractile. No sup- 

 plemental maxillary. Preopercle with its margin usually distinct, 

 not wholly adnate or hidden by skin of head. Gills 4, a slit 

 behind fourth. Pseudobranchise present. Lower pharyngeals 

 separate. No air-vessel. Viscera confined to anterior part of 

 body. Vent not far behind head. Scales various, rarely absent. 

 Mostly cranium becomes twisted, bringing eye over with it. Eyes 



