116 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
the somewhat stronger teeth. The two genera, with perhaps Carpiodcs 
also, should probably be reunited. Three species are known, two in the 
United States and a third in Central America.* buffalo; 
i'/Obc, fish.) 
114. 15. airiis Ag. — BUj-mouihed Buffalo. 
Body much less elevated and less compressed than in B. altus, 
the back not at all cariuated ; axis of body above ventrals about at the 
lateral line, and but very little farther from the dorsal outline than from 
the ventral ; depth 3-34 length. Head very stout, strongly trans- 
versely convex, thicker, larger, and less pointed than in the other, 
about 4 in length. Eye about equal to snout, 5^ in head, much smaller 
than in B. altus. Mouth large, considerably oblique, opening well for- 
wards. Mandible longer than eye. Premaxillary somewhat below sub- 
orbital. Dorsal fin lower and less rapidly depressed than in the next, 
the longest ray scarcely half the length of the base of the fin. Anal fin 
rounded ; its rays not rapidly shortened ; the middle ones not much 
shorter than the longest. Colors very dark; fins all black. Scales 
8-41-7; D. 30; A. 10. Mississippi Valley ; in the larger streams. 
{Carpiodes urns Agassiz, Amer. Journ. Sci. Ai’ts, 1854, 355: Bnhalichthijs 'urus, niger, 
et donasiis Agassiz, Amer. Jouru. Sci. Arts, 1855,193-195; Jordan, 1. c. 209.) 
115. 15. allBls Nelson. — Small-monthed Buffalo. 
Body considerably elevated and conqtressed above; the dorsal region 
subcarinate ; belly thicker ; depth 2J-2f in length ; axis of body above 
the ventrals, below the lateral line, and nearly.twice as far from the back 
as from the belly. Head moderate, triangular in outline when viewed 
from the side, 4 in length. Eye equal to snout, 4-5 in length of head, 
much larger than in B. urus. Mouth quite small, notably smaller and 
more inferior than in B. urus. Mandible about equal to eye. Dorsal 
fin elevated in front and rapidly declined, the highest ray reaching 
much beyond the middle of the fin, the seventh ray about half the 
length of the third or longest. Anal rajxs rapidly shortened behind, the 
middle rays much shorter than the first long ones. Scales 8-30-G; 
*B. meridionalis (Giinther) Jordan. Montli small, inferior, slightly corrugated. 
Depth 3^3i in length. Head 4-44, not much longer than high. L,ye rather small, 
one-tifth of the length of the head and two-fifths that of the snout. Suhorbitals mar- 
row. Anterior dors.al rays not much producc'd, shorter th.an the head. Caudal forked. 
Origin of ventral vertically holow the fourth dorsal ray. l*ector.al fin not extending 
to ventrals. There are 5 longitudinal series of scales between the lateral line and 
the root of the ventral. Coloration uniform. Scales 7-38-7 ; D. 29 ; A. 10. Rio Usu- 
maciuta, Gutitemala. {Giinther.) {jSclerognathus meridionalis GunthoT, vii, 23.) 
