44 TELEOSTEI; EVENTOGNATHL XII. 



hh. Mouth singular, the upper lip not protractile, greatly enlarged; 

 the lower split into two separate lobes; pharyngeal bones, etc. 

 as in Moxostoma LAGOCHILA, 48. 



41. ICTIOBUS Rafmesque. BUFFALO-FISHES. 



(This genus contains an uncertain number of species, very few 

 of which have been yet well defined. They are large, coarse 

 suckers, especially characteristic of the streams of the Mississippi 

 valley. The group much needs careful study, such as could only 

 be given by a collector resident near some large market), (IxjBvs, 

 fish ; ftovs, buffalo.) 



a. Mouth large, terminal, protractile forwards; lips thin; lower pharyngeals 

 and teeth weak. (Scleroynathus Cuv. & Val.) 



66. I. cyprinella (Cuv. & Val.). COMMON BUFFALO-FISH. 

 RED-MOUTHED BUFFALO. Body robust, the outline somewhat 

 elliptical ; head very large and thick ; opercle coarsely striate, 

 nearly half length of head ; lips scarcely plicate ; color dull brown- 

 ish olive, not silvery; fins dusky. Head 3; depth 3. D. 28, A. 9; 

 scales 7-37 to 41-6. L. 3 feet. Miss, valley, etc., common; reaches 

 20 to 40 pounds weight. (Lat., a small carp.) 



aa. Mouth smaller, more or less inferior, protractile downwards, and with 



thicker lips. 



b. Lower pharyngeal bones strong, the teeth comparatively coarse and 

 large, increasing in size downwards ; dusky species, not silvery. 

 (Ictiobus.) 



67. I. urus (Agassiz). RAZOR-BACKED BUFFALO. MONGREL 

 BUFFALO. Body not much elevated, the back not keeled, the 

 axis of the body not much farther from back than from line of 

 belly ; head thicker and blunter than in 1. bubalus ; eye smaller 

 than in /. bubalus; mouth much larger and more oblique, approach- 

 ing that of /. cyprinella, but with lips thicker and plicate, the folds 

 broken up into papillae ; longest dorsal rays scarcely half of base of 

 fin, opercle coarsely striate. Color very dark; fins dark. Head 

 3 to 4; depth 3. D. 30; scales 8-41-7. L. 2 feet. Miss, valley, 

 less common than the others ; certainly different from I. bubalus, 

 but not always distinguishable by me from /. cyprinella, and possi- 

 bly not really different. (Lat., a wild bull.) 



68. I. bubalus (Rafinesque). SUCKER-MOUTHED BUFFALO. 

 SMALL-MOUTHED BUFFALO. Body considerably elevated, the 

 back compressed; axis of body much nearer line of belly than 

 back ; head not very blunt, the mouth small and inferior ; eye 4 to 

 5 in head, rather large ; longest dorsal rays much more than half 

 base of fin in adult; coloration dusky, the fins scarcely black. 

 Head 4 ; depth 2| ; D. 29 ; scales 8-39-6. L. 2 feet. Miss, valley, 

 etc., common. (Bubaliclithys bubalus Agassiz.) (Lat., buffalo.) 



