58 



Family Catostomid.e (The Suckkrs and Buffaloks.) 

 artificial key to the buffaloes and suckers of illinois. 



a. Dors^al fin very long, 25 to 30 rays 



b. Lips thin, not covered with papilla;; scales large. 



c. Colors dark; mouth large. 



d. Anal raj's 9; lips thin; head thicK and rounded; mouth protractile forward; dorsal 



outline much more curved than ventral outline ICTIOBUS CYPRINELLA. 



dd. Anal rays 10; lips thicker; head much enlarged. 



e. Depth ',■! of length I. URUS. 



ee. Depth about two-iifths of length I. bubalus. 



cc. Colors pale, plain ; mouth not large. 



f. Body not deep; depth i.-i to ^4 of lengtbrt Carpiodes carpio. 



ff. Body deep; one-third to four-nintlis of length. 



g. Dorsal with about 24 rays; nostrils near tip of snout C. DIFFORMIS. 



gg. Dorsal with 26 or 27 rays, the first rays elongate more or less; head conical, with 



projecting muzzle C. velifer. 



bb. Lips thick, papillose; scales not large; head very small; body elongate, not much 



compressed Cycleptus elongatus. 



aa. Dorsal fin not elongated, 

 h. Lateral lines complete, 

 i. Lips papillose, 

 j. Body fusiform ; head rounded, 

 k. Scales 95 to 115 in lateral line'. 



kk. Scales 64 to 68 in lateral line, crowded forward Catosto.mus commersonii. 



jj. Body conical; caudal peduncle slender; head pyramidical, concav.e between small 



eyes C. nigricans. 



ii. Lips thin and plicate. 



I. Dorsal of 15 to 18 rays'. 



II. Dorsal fin of 12 to 14 rays. 



m. Caudal fin normal, upper and lower lobes about equal, 

 n. Free margin of dorsal straight. 



MOXOSTOMA AUREOLU.M, PLACOPHARYNX DUQUESNEl. 



nn. Free margin of dorsal more or less incised Moxostoma macrolepidotcm. 



mm. Caudal fin with upper line much longer than the lower; anal tin reaching past the 



caudal", 

 hh. Lateral line incomplete or wanting, 

 o. Sides with regular rows of small black spots; lateral line usually interrupted, 



(wanting in young) Minytrem.\ .mel.^nops 



00. Sides with irregular blotches of large size; a black stripe in voung; lateral line 



wanting Eri.myzon sucetta. 



Ictiobus cyprinella (Cuvier & Valenciennes). — Buflfalo: Red-mouthed Buffalo. 



The common liuffalo-fish of commercial fishermen. Mouth large, protractile fon^-ard; 

 color brownish olive ; opercle ' s the length of the head. Weight 20 to 30 pounds. 



Taken from the Rock, Illinois, and Wabash river basins. Common in large streams. 



Ictiobus uriifi (Agassiz). — Mongrel Buffalo. 



Back not much elevated and not compressed into a keel above, but rounded in cross- 

 section. 



Distributed about as /. cyi^rineUa, though not so common. 



IcUobus bJibalKS (Ratinesque). — Small-mouthed Buffalo: Razor-backed Buf- 

 falo. 



Depth of body five-elevenths of length; back thin; belly thick. 

 Common in large streams and in lakes and in lakes and sloughs. 



Carpiodes atrpi (Rafinesque). — Carp Sucker. (63). 



Perhaps not rare in large rivers; our collections not, however, as yet carefully studied. 



Carpiodes difforinis Cope. (70) 



Identified in our Illinois river collections. Probably frequently confused with the next 

 species. 



Carpiode!< velifer (Rafinesque.). — Quillback; Spearfish: Skipjack. (70) 



Known by tlie excessive elongation of tlie first rays of the dorsal fin. 

 Very abundant everywhere, but almost worthless as food. 



CiideptHs elon(jatiis (Le Sueur). — Black Horse: Missouri Sucker. 



Formerly abundant in the Illinois river; but now only occasionally taken. The single 

 specimen taken in our collections of the past three years conies from the mouth of tJreen 

 river. A siiecimen was obtained also from the Little Fox river, at Philipstowii, 111., in 18S2. 



Cato-stomus commersonii (Lacepede). — Common Sucker: Fin-scaled Sucker; 

 Black Sucker. (76) 



The number of scales varies greatly, giving rise possibly to several more or less distinct 

 varietal forms. 



^Ca/osto»!iis catostomus: of uncertain occurrence in Illinois. 

 • Moxosloma aiiisiirum: of uncertain occurrence in Illinois. 

 ^ Moxosio?na dreviceps: of uncertain occurrence in Illinois. 



