328 PISHES. 



mally 12 ; supraoccipital bone free behind ; head long, broad, 

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

 anal fin short, of 12 to 14 rays ; ventrals with 9 rays ; cau- 

 dal fin truncate, its numerous rudimentary rays recurrent 

 above and below the caudal peduncle ; number of vertebra? 

 increased ; body elongate, covered with thick skin. 



PELODICIITHYS, 3. 



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

 or less perfectly continuous with the caudal fin ; supraocci- 

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

 with 11 to 20 rays; caudal fin 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. 



NOTURUS, 4. 



/. ICHTHMLURUS, Rannesque. CHANNEL CATS. 



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

 posterior margin. 



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

 the body ; its rays 32 to 34 ; body slender. 



1. /. furcaius, (Cuv. &Val.) Gill. FORK-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 fin shorter, 3i to 4 in length ; its rays 27 to 30 ; body 

 robust, compressed. 



2. /. 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 29. 



3. I. punctatus, (Raf.) Jor. COMMON CHANNEL CAT. 

 BLUE CAT. WHITE CAT, etc. Head moderate, about 4 



