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PISCES. 



Subgenus Morrhua, Cuv. Cod. 



Three dorsal fins ; two anais ; a cirrus at the point of the 

 lower jaw. 



Subgenus Merlangus. Whiting. 



The same number of fins as the Cod, but no cirrus. 



Subgenus Merluccius, Cuv. Hake. 



Two dorsals ; only one anal ; no cirrus. 



Genus II. Pleuronectes, Lin. 



Commonly called Flat Fish, have a character unique among 

 vertebrated animals, consisting in the want of symmetry in 

 the head, where both eyes are on one side, which remains 

 uppermost while the animal is swimming, and which is 

 always deeply coloured, while that in which the eyes are 

 wanting is whitish. The rest of the body participates a little 

 in this irregularity. The two sides of the mouth are not 

 equal, and the pectorals rarely so. The body is strongly 

 compressed and vertically elevated. The dorsal extends 

 throughout the length of the back; the anal occupies the 

 under part of the body, and the ventrals almost seem to con- 

 tinue it before while they are in fact often united with it. 

 There are six rays to the gills, and no natatory bladder ; they 

 seldom quit the bottom of the water. Three remarkable sub- 

 genera. 



Subgenus I. Platessa, Cuv. Plaice. 



A range of obtuse trenchant teeth in each jaw ; generally 

 teeth enpavés to the pharyngeals (arranged like paving stones). 

 The dorsal only advances as far as the top of the other eye, 

 and leaving, as well as the anal, an interval between it and 

 the caudal. Generally eyes on the right. 



Subgenus II. Rhombus, Cuv. Turbot. 



Teeth small and crowded, like those of a card, in the jaws 

 and pharynx; dorsal advancing towards the edge of the upper 

 jaw, and extending, as well as the anal, to very near the cau- 

 dal ; eyes almost always to the left. 



Subgenus III. Solea, Cuv. Sole. 



Mouth twisted, and as if distorted, to the side opposite the 

 eyes, and furnished on this side only with teeth en velours 



