328 PISHES. 



mallylS; supraocoipital bone free lieliind; head long, broad, 

 and flat; mouth large, the lower jaw always the longer; 

 anal fln short, of 13 to 14 rays ; ventrals with 9 rays ; cau- 

 dal fin truncate, its numerous rudimentary rays recurrent 

 above and below the caudal peduncle; number of vertebrae 

 increased ; body elongate, covered with thick skin. 



Pelodichthts, 3. 

 ** Adipose fln long and low, keel-like, adnate to the back, more 

 or less perfectly continuous with the caudal fin; supraocoi- 

 pital bone free behind; branchiostegals 9; anal fln short, 

 with 11 to 20 rays; caudal fln rounded, with numerous rudi- 

 mentary rays recurrent on the caudal peduncle ; ventral rays 

 usually 9; form various, but body usually more or less 

 elongate, depressed in front, compressed behind, covered 

 with a thickish but semi-transparent skin ; size small. 



NoTTmus, 4. 



/. ICHTHMLURUS, Rannesque. Channel Cats. 



* Eye small, anterior, the middle of the head being behind its 

 posterior margin, 

 f Anal fln extremely elongate, its base one-third the length of 

 the body; its rays 33 to 34; body slender. 



1. /. /i/rcatos, (Cuv. &Val.)Gill. Foek-Tailed Chan- 

 nel Cat. Head small, 4^- in length, the slope from dor- 

 sal to snout somewhat concave; spines long. Missis- 

 sippi Valley, and Southwest. 



tf Anal fln shorter, 3i to 4 in length ; its rays 37 to 30 ; body 

 robust, compressed. 



3. /. robustus, Jordan. Robust Channel Cat. A 

 stout, deep species, with shorter spines; dorsal region 

 elevated; the profile concave. Mississippi Valley. 



** Eye large, median, the middle of the head falling before its 

 posterior margin ; anal short, not greatly elongate, its rays 

 25 to 39. 



3. /. punctatus, (Raf.) Jor. Common Channel Cat. 

 Blue Cat. "White Cat, etc. Head moderate, about 4 



