April, iQio. Fishes of Chicago — Meek and Hildebrand. 241 



flat or slightly convex; mouth terminal, the upper jaw slightly the 

 longer; maxillary barbels long and slender, their tips reaching past 

 gill opening; eye nearer upper than lower surface of the head, its di- 

 ameter 4 to 8 in head; dorsal fin high, its distance from snout 2.5 to 

 2.7 in length; caudal fin deeply forked, the upper lobe longer and 

 more slender than the lower. 



Color light grayish green above, below silvery; back and sides with 

 small, round, irregularly distributed dark spots. 



This fish reaches a weight of 15 to 20 pounds, but those usually 

 taken for the market seldom reach a weight of 4 or 5 pounds. 



It inhabits clear water from the Great Lake Region to Louisiana 

 and Mexico, preferring river channels to still water. An excellent food 

 and a fair game fish. 



Deep River, Liverpool, Indiana. 



Genus Ameiiirus Rafinesque. 



Bullheads; Horned Pouts. 



Body moderately elongate, robust anteriorly, compressed posteri- 

 orly; supraoccipital bone separate from the second interspinal buck- 

 ler, forming a break in bony bridge from snout to dorsal fin ; mouth 

 large; teeth in jaws in broad bands, the band in upper jaw not form- 

 ing backward extensions; caudal fin short, its margin rounded to 

 slightly forked. 



a. Caudal fin moderately forked; anal rays 24; species large. 



lacustris, 242 

 aa. Caudal fin rounded, truncate, or slightly emarginate; species 

 small, usually less than 12 inches in length. 



b. Anal rays 24 to 27; caudal fin rounded. natalis, 242 

 bb. Anal rays 17 to 24; caudal fin slightly emarginate. 



c. Anal rays 21 to 24; pectoral spine in young with 5 to 10 well 

 developed teeth on its posterior edge, these reduced in size in 

 adults, the number increasing to from 15 to 20; anal fin with 

 membrane and rays about equally colored, the former slightly 

 the darker on distal third. nebulosus, 242 



cc. Anal rays 17 to 20; pectoral spine at all ages entire or slightly 

 roughened behind, or rarely in adults with 5 to 10 obscure, 

 weak, and blunt teeth on its posterior edge; anal fin with the 

 membranes uniformly colored and darker than the rays. 



melas, 243 



