66 VERTEBRATE ANIMALS OF THE UNITED STATES 



C. eos Cope. Similar to C. erythrogaster, but with a slenderer body, 

 the lateral line often wanting and the two lateral black bands uniting in 

 the caudal peduncle : east of Alleghenies. 



C. dakotensis Evermann & Cox. Similar to C. erythrogaster, but 

 smaller and stouter and without the black spot on the tail; rays of dorsal 

 fin 8; anal 8; scales about 8o, 24 in a cross series; teeth 4-4: Missouri 

 River basin in Nebraska and South Dakota. 



C. oreas Cope. Similar to C. erythrogaster, but with a somewhat 

 different color pattern, the upper band ending in the caudal black spot, 

 the lower band ending at the anal fin; scales 67: head waters of the 

 Roanoke River and the Tennessee; abundant. 



Fig. 32. — Chrosomus erythrogaster {from Fishes of Illinois). 



8. Hybognathus Agassiz. Body elongate; teeth 4-4, with little or 

 no hook ; scales large ; rays of both dorsal and anal fins usually 8 ; lateral 

 line complete: 4 species. 



H. nuchalis Ag. Silver minnow. Length 150 mm.; head 4.5; 

 depth 5; color olivaceous green; sides silvery; rays of anal fin 7; scales 

 5-38-4, 12 to 14 scales before the dorsal fin: New York to the upper 

 Missouri; southward to Georgia and Texas; common in large rivers. 



H. hayi Jordan. Like H. nuchalis, but with a slenderer body; 

 scales 5-36-3: lower Mississippi region, northward at least to Memphis. 



H. regia Girard. Similar to H. nuchalis, but with a shorter and 

 deeper head: Lake Ontario and New Jersey to James and Neuse Rivers, 



H. hankinsoni Hubbs. Similar to H. nuchalis, but with a shorter 

 head and darker color: Great Lakes basin; west to Colorado. 



9. Dionda Girard. Teeth short, hooked; body elongate; scales 

 large: 6 species, 2 in Mexico. 



D. serena (Girard). Length 60 mm.; color dusky with a black 

 lateral band; scales ,5-32 to 34-3; teeth hooked: western Texas. 



