ICTIOBUS 71 



and heavy, its length 3.7 to 4, depth 4 to 4.8, width 4.9 to 5.6 in length 

 of body; snout very blunt and broadly rounded, its profile continuous 

 with that of frontal region; interorbital space *2 to 2.3 in head; mouth 

 moderate, considerably smaller than in last species, and but slightly 

 larger than in next species, sub- 

 terminal, protractile forward and 

 downward, as a rule but little 

 oblique, the edge of the mandible 

 falling considerably below medi- 

 an axis, level of upper lip about 

 midway between chin and lower 

 margin of orbit ; angle formed by 

 articulation of mandible with / 

 quadrate evident, but less prom- >, ■ 

 inent than in cyprinella; lips 



rather thin, but less so than in ""^^^v- , .' / 



last species, theupper faintly, the """^^ter •""■','"" 



lower rather coarsely, striated; ^^' ■=£,», 



eye S.l to 6.6 in head, situated 



well upward and forward; oper- Fig. 15 



cles not so broad as in the last. 



Dorsal rays 29 or 30, the longest considerably less than \ base of fin; 



other fins about as in the preceding species, the caudal not quite so 



deeply forked. Scales 7 or 8, 36-40, 6 to 8; lateral line complete, less 



flexuose posteriorly and not so abruptly elevated in front of dorsal as in 



cyprinella. 



Spring males without tubercles. 



The mongrel buffalo appears to vary somewhat more than either 

 1. cyprinella or bubalus, but we have met with no cases which appear 

 to show intergradation with either. This species seems to be al- 

 ways distinguishable from the former by its much smaller and less 

 oblique mouth, the upper lip falling far below the level of the low 7 er 

 margin of the orbit, and by the coarsely striate lower lips; from the 

 latter by the more elongate and less compressed body, and by the 

 broad rounding of the frontal region and of ±*he back in front of the 

 dorsal fin. 



Distributed throughout the Mississippi Valley practically as the 

 red-mouth is, but less abundantly. 



This is a large species, sometimes exceeding 50 pounds in weight, 

 though commonly less than 20. It resembles the red-mouth in 

 habits and value. 



The same may be said with respect to its food, our 17 specimens, 

 well distributed as to time and place of capture, having taken ratios 

 of animal and vegetable food almost identical with those of cypri- 

 nella — 67 per cent, and 33 per cent, respectively. There was a 

 larger ratio of mollusks and of insects — the -latter 42 per cent. — but 



