FISHES OF LAKE SUPERIOR. 281 



PIMELODUS FELIS, Agass. 



The general form is that of most species of the genus, neither 

 thick, nor elongated. The abdomen is prominent in the space 

 contained between the branchiostegal apparatus and the ventrals. 

 The curve of the back rises to the height of the dorsal, whence 

 it slopes rapidly upon the head. The body is very compressed 

 from behind the dorsal and ventral fins to the tail. It is com- 

 pletely bare, with a punctulated appearance, caused by the aqui- 

 ferous holes w.hich open at the surface of the skin, and which 

 are especially numerous on the anterior region and on the head. 

 The lateral line is straight, ascending from the middle of the 

 caudal to the upper angle of the opercular apparatus. The head, 

 from the occiput, forms the fifth part of the whole length, whilst 

 from the posterior margin of the operculum to the end of the snout 

 it constitutes only one fourth. The head is longer than it is broad, 

 and forms a regular oval, truncated behind in the occipital region 

 and elliptical in the anterior circumference. The mouth extends as 

 far back as the eyes ; the lips surround it under the form of a fleshy, 

 elastic swelling, in the middle of the jaws only ; but at their reunion 

 with the angles of the mouth they grow thinner, widen and flatten, 

 and form a kind of funnel, which enlarges, for a third at least, the 

 opening of the mouth. The teeth are arranged like those of a 

 card, and distributed irregularly upon the circumference of the 

 jaws. They vary in length and size, but are all acute. On the 

 lower jaw they extend much more backwards in the mouth than on 

 the upper jaw, where they do not extend beyond the basis of inser- 

 tion of the maxillary barbels. These latter, two inches long, reach to 

 the posterior margin of the preoperculum. They follow the upper 

 circumference of the cutaneous funnel at the angles of the mouth 

 for the extent of six-eighths of an inch. Hard, horny and flattened 

 at their basis, they grow gradually softer and more slender towards 

 their termination. The nostrils are situated on the upper surface of 

 the head, at a distance of half an inch from the end of the snout. 

 Their opening, of oblong form, measures one-eighth of an inch in the 

 direction of the greatest diameter. The barbels which arise from 



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