io Field Columbian Museum — Zoology, Vol. V. 



the posterior finely denticulate; length of pectoral spine if in head; 

 caudal fin deeply forked, the upper lobe the longer. 



Color dark bluish above, much lighter below; the dark color 

 on lower half of sides and on fins made up of small dark punctula- 

 tions; ventral and pectorals and distal half of anal nearly black; 

 caudal and dorsal with tips of rays black; bellv white. 



One specimen (type) from Perez. 



Subfamily Ichthyaelurinse. 



4. Ichthyselurus Rafinesque. 

 Channel Cats; Bagres. 



Ictalurus Rafinesque, Ichth. Ohiensis, 61, 1820. (Type, Pimelodus 

 niaculatus Rafinesque = Ictalurus punctatus Rafinesque.) 



Body elongate, slender, compressed posteriorly; head slender and 

 conical; supraoccipital bone or process prolonged backward, its 

 emarginated apex receiving the accuminate anterior point of the 

 second interspinal, thus forming a continuous bony ridge from the 

 head to the dorsal spine; mouth small, terminal, the upper jaw the 

 longer; teeth in a short band in each jaw; dorsal fin with one spine 

 and usually 6 soft rays; adipose fin short, with free posterior margin 

 opposite posterior margin of anal fin; anal fin long, 25 to 35 

 -rays; pectoral spine strong, retrorse-serrate within; caudal fin elon- 

 gate, deeply forked. 



The fishes of this genus live chiefly in river channels. As food 

 fishes they are superior to other members of the catfish family in 

 North America. 



KEY TO THE SPECIES OF ICHTHY/ELURUS. 

 a. Anal fin very long, its base nearly V$ its body, page 



its rays 32 to 35 jurcatus 10 



aa. Anal fin shorter, its rays 25 to 2Q. 

 b. Barbels long, extending considerably beyond 



gill opening; anal rays about 26 punctatus 11 



bb. Barbels short, the longest only reaching gill 



opening; anal rays 28 or 29 meridiofialis 11 



5. Ichthyselurus furcatus (Le Sueur). Chuckle-headed Cat. 



Pimelodus jurcatus Le Sueur, in Cuvier & Valenciennes, Hist. 



Nat. Poiss., v, 136, 1840; New Orleans. 

 Pimelodus afjinis Baird & Girard, Proc. Acad. Nat. Sci. Phila., 



1854, 26, Rio Grande: Girard, Mex. Bd. Sur., 32, pi. xvi, 1859; 



mouth of the Rio Grande, at Brownsville, Texas. 

 Amiurus jurcatus Gvmther, Cat., v, 103, 1864. 



