208 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
and equal to those above it. D. 85 A. 7; scales 13-70-13. Tributaries 
of the Itio Grande in Colorado and New Mexico. {Cope.) 
(Bhinichthya maxilloaus Cope & Yarrow, Zool. Wheeler’s Expl. W. lOOtli Mer. v, 644, 
1877 (not of Cope, 1864); Cope, Amer. Nat. July, 1879, 441.) 
316. R. obtciSdS Agassiz. — Broton-noaed Dace. 
Very similar to R. atro7iasus, but usually rather stouter, the barbel 
more distinct, the head a little shorter, and the coloration somewhat 
different. Back olivaceous, mottled with darker; sides with a rather 
faint brownish band, margined above and below with paler; belly sil- 
very; a dusky blotch in the middle of the base of the dorsal fin; males 
with the iiectoral fins enlarged, and with the lateral band rosy. Head 
4; depth 4^. D. 7; A. 6 ;* scales 4-63-8; teeth 2, 4-4, 2. L. 3 inches. 
Wisconsin to Georgia ; abundant in clear brooks. Probably a variety 
of the next species. 
(Agassiz, Amer. Journ. Sci. Arts, 1854, 357; Giinther, vii, 190; Jordan, Ann. Lyc. 
Nat. Hist. N. Y. 1876, 331 : Bhinichthya lunatua Cope, Proc. Acad. Nat. Sci. Phila. 1864, 
278 : Bhinichthya meleagria Agassiz, Amer. Journ. Sci. Ai-ts, 1854, 357 : Bhinichthya ineleagris 
Nelson, Bull. Ills. Mus. Nat. Hist, i, 46: Bhinichthya meleagria Gunther, vii, 190.) 
SIT. R. atroBiasns (Mitch.) kg. — Black-noaed Dace. 
Body moderately elongate, little compressed. Head moderate, rather 
broad and flattish above. Snout moderate. Month small, horizontal, 
subterminal, the lower jaw included, barbel minute but iirobably always 
present, uj)per lip on the level of the lower part of the pupil, max- 
illary not reaching nearly to the eye. Eye small, nearly median, in 
snout, 4^ in head. Fins rather small; dorsal fin well back. Scales 
quite small, somewhat imbedded. Lateral line somewhat decurved. 
Color blackish above; some of the scales irregularly darker ; a black 
band passing from snout through eye and along the sides of the 
body ; a pale streak below this ; belly silvery ; males in spring with the 
lateral band and the lower fins, and sometimes the whole body, bright 
crimson ; males in late summer with the lateral band scarlet or orange, 
the red color growing fainter later in the season. Head 4 ; depth 4J. 
D. 7 ; A. 7 ; Lat. 1. 64 ; teeth 2, 4-4, 2. L. 3 inches. New England to 
Ohio and Virginia ; very abundant in clear brooks and mountain streams. 
{Cyprinua atronaaua Mitch. Trans. Lit. & Phil. Soc. i, 460; Giinther, vii, 191.) 
60.— AGOSIA Girard. 
(Girard, Proc. Acad. Nat. Sci. Phila. 1856, 186; type Agoaia chrysogaater Grd.) 
Body moderately elongate. Mouth moderate, normal, the premax- 
illaries protractile, the maxillaries with a terminal barbel. Teeth 4-4^ 
