IIG 



I'LEURONECTIDiE. 



T!!E FAMILY OF FLAT FISHES. 



A TOTAL want of nniformiry bet-ween the sides of the Lead, 

 and also generally of the body. Eoth of the eyes are on one 

 side of the head, while the nostrils generally maintain their 

 position in pairs on each side of the summit. The mouth is 

 twisted, so that the two corners do not answer to each other, 

 and within the mouth there is generally a veil or cross mem- 

 brane above and below. The body is much compressed; one 

 side bearing colour, the other without it, and the structure of 

 the skin differs in each. The abdominal cavity very short, 

 but the lobes of roe are contained for the most part in a 

 recess which passes backward between the muscles towards 

 the tail. The vent close to or enclosed between tlie ventral 

 fins, which are near the throat. The fins nearlv encircle the 

 body, and the dorsal fin begins on the top of the head or in 

 front of it. 



In most if not all of these fishes the spinous pi-ocesses of 

 the vertebrae which suj)2:)ort the rays of the dorsal fin, and are 

 anterior to the pelvis, are turned forward for that purpose; 

 while those of the vertebrae on the same line of the back that 

 are near the tail are directed backward. On tlie abdominal 

 side all the spinous processes behind the abdomen itself are 

 directed more or less backward. It is an essential pai't of the 

 structure of these fishes that the superior and inferior processes 

 of the vertebrae are very long% and those of the sides very- 

 short; but in the Carter, and perhaps in others of this family 

 which possess a lengthened form, while the superior and 

 inferior processes are comparatively shorter, the lateial processes 

 are somewhat more developed. In the Topknot the spinous 

 processes of the vertebrae are remarkably long, and anterior 

 to the first of these processes there are numerous (what we 



