200. With two dark stripes along each side; lateral line incomplete or lack' 



ing; pharyngeal teeth 4'5 or 5-5; scale count usually over 50 201. 



With one or no stripe on side; lateral line complete; pharyngeal teeth 



4-4; scale count under 50 204. 



201. Stripes on sides not extended to form dark spots on tail; S. D. and 



Nebraska 



Chrosomiis da\otensis E. & C. 

 One or both stripes on each side extended to form a spot on the tail fin 



202. 



202. Both lateral stripes on each side united on the tail; Susquehanna River 



southwards 



Chrosomus eos Cope 

 With one stripe on each side extending on to the tail 203. 



203. With the lower lateral stripe extending on to the tail; breeding males 



with red bellies and yellow fins; Colorado to the St. Lawrence River 

 Chrosomus erythrogaster Raf . Red-bellied Dace 

 With the upper lateral stripe extending on to the tail; upper Roanoke 



and Tennessee Rivers 



Chrosomus areas Cope 



204. Color greenish, with a dark lateral stripe from snout to tail; no sym' 



physeal protuberance; Illinois to Wyoming and the Ozarks 

 Dionda nuhila (Forbes) 

 Color gold or silvery, unstriped; with a prominent hard protuberance at 

 the tip of the inside of the lower jaw 205. 



205. Sides with a golden sheen; dorsal fin evenly rounded; N. Y. to Montana 



and southward westerly to Colorado 



Hyhognathus han\insoni Hubbs Brassy Minnow 

 Sides silvery; posterior rays of dorsal fin abruptly shorter than anterior 

 rays; eastern and central states to Texas 



Hyhognathus nuchahs Agassiz Silvery Minnow 

 (Includes H. regius Girard) 



206. Abdomen between the pelvic fins and the anal fin compressed to a keel' 



like edge, which is unsealed (difiicult to see in young specimens) ; anal 

 rays eleven to fourteen; scale count about fifty; pharyngeal teeth 5 '5; 

 six to eight inches long; (fins red in subspecies crysoleucas, the eastern 

 form, not red in subspecies auratus, the western form) ; Maine to Texas 



l\[otemigonus crysoleucas (Mitchill) Golden Shiner 



J\lotemigonus auratus Raf. 

 Abdomen not so; anal rays twelve or less; other characters various 207. 



207. Teeth on the pharyngeal bar 4-5 or 5-5 in the main row; scale count 



usually over 40, often over 50 (35 to 45 in a few species with extreme' 

 ly small mouths or with the lateral line incomplete to absent) ; size 

 various 208. 



Main row of pharyngeal teeth 4-4; scale count less than 60, usually less 

 than 50; lateral line incomplete in a few species; usually small fishes 



226. 



208. With three pharyngeal teeth in the smaller row; a moderate sized Eu' 



ropean species introduced into the eastern states 



281 



