66 



VERTEBRATE AXIMALS OF THE UNITED STATES 



L. exilicauda Baird & Girard. Hitch. Length 300 mm.; head 

 4.6; depth 3.3; color dark, speckled, with silvery sides; rays of dorsal fin 

 10; anal 12; scales 13-64-18: Coast Range, from Monterey to Clear 

 Lake; common. 



7. Chrosomus Rafinesque. Body moderately elongate; size small; 

 teeth 5-5 or 4-4, moderately hooked; scales minute; lateral line short 

 or wanting: 4 species. 



C. erythrogaster Raf. Red-bellied dace (Fig. 32). Length 75 mm.; 

 head 4; depth 4; color brownish oHve above, often with black spots; 

 sides and belly silvery, with 2 black lateral bands, one running from 

 the snout through the eye and cur\dng down along the belly to a black 

 spot in the tail; male in spring with yellow tins and bright scarlet belly; 



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



teeth 5-5; rays of dorsal fin 7; anal 8; scales 18-85-10: central Xew 

 York and Pennsylvania to Dakota; southward to Alabama; common 

 in clear, small streams; one of the brightest of the minnows. 



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: Susquehanna River. 



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 80, 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: abundant. 



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: 9 species, 2 in Mexico. 



