Idus idus Linn. Golden Ide 

 Pharyngeal teeth in one row or with one or two teeth in the smaller 

 row 209. 



209. Mouth extremely small, not extending past a vertical from the nostrils; 



scale count about 40 210. 



Mouth somewhat larger; scale count over 40 in most but not all 



species 212. 



210. Lateral line almost absent; with a distinct black blotch at the base of the 



tail fin; southern states 



Opsopoea hollmani (Gilbert) 

 Lateral line variously incomplete to complete; black blotch at base of tail 

 fin obscure or absent 211. 



211. Lateral line almost complete; usually with a dark lateral stripe, with dark 



spots above and below; southeastern U. S. 



Opsopoeodus emiliae Hay Southern Pug-nosed Minnow 

 Opsopoeodus emiliae emiliae Hay 

 Lateral line variously incomplete; sides plain; Great Lakes area to Texas 

 Opsopoeodus megalops (Forbes) Northern Pug-nosed Minnow 

 Opsopoeodus emiliae megalops (Forbes) 



212. Teeth on the pharyngeal bar in one row; anal rays seven or eight; lateral 



line incomplete or decurved Roaches 213. 



Teeth on the pharyngeal bar in two rows; anal rays seven or more; later' 



al line various Daces 215. 



213. Mouth scarcely oblique; scale count about 54; sides dark spotted or dark 



striped; about five inches long; Gal. and Nevada 



Hesperoleucus symmetricus (B. 5? G.) Roach 

 (Rutilus symmetricus (B. &' G.) ) 

 Mouth very oblique; often larger 214. 



214. Color plain or spotted; scale count about 56; about a foot long; Cal. and 



Nevada 



Siphateles olivaceus (Cope) 

 (Rutilus olivaceus (Cope) ) 

 With a dusky band along each side; scale count about 48; about eight 

 inches long; Oregon and California 



Siphateles hicolor (Girard) Roach 

 (Rutilus hicolor (Girard) ) 



215. Lateral line absent or incomplete (do not confuse with lateral band or 



stripe) 216. 



Lateral line complete 219. 



216. No trace of lateral line; with a dark lateral stripe; scale count 35 to 40; 



about an inch and a half long; Utah 



lotichthys phlegethontis (Cope) Little Dace 

 (Leuciscus phlegethontis (Cope) ) 

 Usually with some lateral line 217. 



217. With scattered dark scales forming a spotted pattern; scale count about 



50 to 75; Lake Erie and southwards 



Margariscus margarita (Cope) Pearl Minnow 



282 



