CATOSTOMID^E. CIX. 325 



3. B. bubalus, Agassiz. SMALL - MOUTHED BUFFALO. 

 Body considerably elevated and compressed above; the 

 dorsal region sub-carinate; belly thicker; depth 2f in 

 length; axis of the body above the ventrals, below the 

 lateral line and nearly twice as far from the back as the 

 belly; greatest depth of body at beginning of dorsal, 

 which is in advance of ventrals, and a trifle nearer the 

 snout than the caudal; head wide, rounded across the 

 top, wider above eyes than across cheeks; interorbital 

 space 2 in head; head 4 in length of body, its greatest 

 depth 1^ in its length; eye=snout 4 in head, much 

 larger than in J3. niger; mouth small, notably smaller 

 than in J3. niger, and with thinner lips, which are granu- 

 lated and feebly plicate; mandible about equal to eye; 

 pharyngeal bones very strong, with large teeth, which 

 grow larger downward; intestinal canal long, longer 

 than body; a decided occipital depression; head trian- 

 gular in outline, viewed from the side; ante-orbital 

 region strongly elevated and curved; length of top of 

 head 2f in distance from snout to occiput; nostrils large; 

 scales 8 40 6 in two specimens, 8 39 6 in one, 7 

 39 5 in the fourth; fin rays D. I, 28 in two, I. 29 in 

 rest; A. I, 10; V. 10; dorsal elevated in front and rap- 

 idly declined, the seventh ray half the length of the 

 third or longest; the latter reaches to the base of the 

 18th ray, or more than half the base of the fin; anal 

 reaching caudal, its rays rapidly shortened; pectorals 

 shorter than anal, anal than ventrals, all than head. 

 Mississippi Valley, abundant. (JS. lubalus, Ag., not 

 C. bubalus, Raf.) 



