April, 1910. Fishes of Chicago — Meek and Hildebrand. 251 



Body short, compressed; the dorsal region much arched; snout 

 small, wholly inferior; lips weakly plicated, the halves of the lower 

 meeting at a rather sharp angle, tip of lower lip scarcely in advance 

 of the nostrils; interorbital space 2.2 to 2.5 in head; snout short, 

 very blunt, its length 3.9 to 4.5 in head; nostrils near tip of snout; 

 anterior dorsal rays as long as or longer than the fin; lateral line 

 complete. 



Color silvery, darker above. 



This fish seldom reaches a length of more than 1 2 inches. 



It occurs in the Ohio Valley and westward in the larger streams. 



Carpiodes velifer (Rafinesque). Quillback; Silver Carp. 



Head 3.6 to 4.0; depth 2.7 to 3.0; D. 27 to 30; A. 9 to 10; scales 

 39 or 40. 



Body ovate, compressed; dorsal region much arched; mouth small, 

 slightly oblique; lips weakly plicate, the lower halves meeting at a 

 sharp angle; tip of lower lip far in advance of nostrils; interorbital 

 space 2.3 to 2.5 in head; snout long, bluntly pointed, its length 2.9 

 to 3.5 in head; nostrils much nearer eye than tip of snout; anterior 

 dorsal rays about as long as the fin; lateral line complete. 



Color light olive above, sides silvery; fins pale. 



Length about 12 inches. 



This species occurs in the smaller rivers and creeks from Ohio 

 to Iowa and southward. It spawns in April. Similar in size and 

 appearance to the preceding. 



Genus Eriinyzon Jordan. 



The Chub Suckers. 



Body elongate, more or less compressed; head short; mouth 

 subinferior, slightly oblique; upper lip protractile, lower lip plicate, 

 its halves meeting in an acute angle; no anterior fontanelle, the 

 posterior well developed ; pharyngeal bones weak, the teeth small and 

 slender, rapidly decreasing in length upward ; air bladder in two parts ; 

 lateral line wanting. 



Erimyzon sucetta (Lacepede). Chub Sucker. 



Head 3.5 to 4.1 ; depth 3.1 to 3.9 ; D. 9 to 12 ; A. 7 ; scales 36 to 45 



Body oblong, compressed, becoming deeper with age; head short; 



mouth subinferior, small, slightly oblique; lower lip strongly plicate, 



its halves meeting at an acute angle; eye large, 3.8 to 5.8 in head; 



