64 



Erifiiinhn huccaUi Cope. 

 Body cylindrical; in general appearance like the straw colored minnow (^ A'. ^/^««rM/). 

 Lower jaw much enlarged, with mucous cavities which appear on the outside as vitreous 

 streaks; eyes directed slightly upwa.d, giving to the f5sh a peculiar watchful expression. 



Aljundant in the upper Wabash basin; taken also from the Iroquois basin near Watseka. 

 Its occurrence in the latter place due probably to its crossing the low divide near Hoopeston 

 by aid of high water or the changes of wa'er courses through artificial drainage. 

 PheiKicohius ininihiUs (Girard). — Sucker-mouth Minnow. 



Mouth inferior; upper lip thickened outwardly and sucker-like; form of body similar to 

 that of the common red-horse. This species and P. scopifer (Cope) are not readily distinguish- 

 able in our collections. The first is described with 48 to hi scales in the lateral line, the second 

 with 43 to 45, this being the usual basis of separation. (-)ur specimens are intermediate, having- 

 from 4.3 to 50 scales. We have therefore called thetn collectively P. niirabilis. 



Taken in 140 localities, in moderately swift water, throughout the State. 



Rhinichthyx atronttHiis (Mitchill). — Black-nosed Dace. 



In general appearrnce verv much like the Stone roller {Campostoma anomalum), but with 

 a barbel at each corner of the mouth : the males differing in having a stripe on the side which 

 varies with seasons from crimson to pale sal men -color. 



Found in rapid streams, widely distributed throughout the State, but nowhere common. 

 Not yet taken from tributaries of the Wabash or of Lake Michigan. 



KEY TO ILLINOIS SPECIES OF THE GENUS HYBOPSIS. 



a. Small slender species with mouth inferioi ; usually silvery. 



b. Barbels 4 H . tetr .\xe.mus . 



bb. Barbels 2. 



c. Eve small, its length less than ^.-j that of head. 



d. Length of eve about ?4 of head: length or barbel about I3 of head; .scales every- 



where dusted with black specks over silvery color H. HYOSTOMUS. 



d'd. Length of eye about 1-6 of head; length of barbel about 3-5 of eye; fine black 



specks on posterior bt-rder of scales of back; lower lobe of caudal dark, with 



white border.' 

 cc. Eye large, its length about I3 or more of head; sides blotched: dusky or silver>-. 



e. Mottled with black or brown. 



f . Scales 16 to 18 before dorsal H . dissimilis. 



ff. Scales 20 to 24 before dorsal H. uatacga. 



ee. Not mottled; silvers-, dusted with dark specks, or scales edged with dusky. 



g. Head large, length Ji that of body, flattened above: muzzle bluntly decurved; eye 



i;3 length of head H. amblops. 



gg. Head short, length less than I4 of body : cheeks nearly vertical; a tieshy pad on 



end of snout H. storeriaxus. 



aa. Large species, with rather heavy body : mouth large, almost terminal; notsilverj-. 



H. kentcckiensis. 



HyJiopsis tctraiicmMS (Gilbert). 

 The only native minnow with four barbels. A small, slender, silvery fish with large fins. 

 Length 2 inches. 



iJiy/>o/).si.s hyostoiniis (Gilbert). 

 Snout long and acute, projecting half its length beyond the mouth. A silverj- minnow. 

 Specimens referred to //. hyostomus have been taken from the Illinois river at Havana and 

 Naples, and from the middle fork of the Big Vermilion river on the Champaign-Ford county 

 line. 



Hybfypsis dinsiinlUs (Kirtland\ — .Spotted Shiner. 

 In form much like the sucker-mouth minnow (Phenacodius^: length 3 to 4 inches. Dis- 

 tinguished readily from Phenacobius by the pair of barbels, the form of the lip, and the dark 

 irregular mottlmg of the back and sides. t - n 



Taken from Kock river at Rockford and Dixon, from Tomahawk creek near LaSalle. 

 Spoon river at London Mills, Sangamon river at Decatur, and Embarras river at Charleston. 



Hyhopsis tvdUunja Jordan & Evermann. 



Like H. dissimi/is in many respects; but with a bluish stripe passing around the snout, the 

 stripe bearing 8 to 12 small black spots. 



Hyhopx'is (imhlops (Katinesqvie). — Silver Chub; Big-eye Chub. 



Head large and flattened; eyes directed upward; color silvery. , . 



Not infrequent in the streams of the Wabash and Ohio basins; taken five times from the 

 middle course of the Illinois river and once from near its mouth; taken also frorn near the 

 mouth of Rock river, from a pond near Quincy, from the Sangamon river, and five Umes 

 from the Ivaskaskia river. 



Hyhopsi,^ stovcrhDiux (Kirtland). 



Second in size among the species of this genus. A silvery chub, in appearance and size 

 somewhat like //i7'(i!r"'"'/'?'.f >na/mlis. Mouth inferior, overhung by the snout, which has a 

 peculiar Heshv pad on the end: barbels minute: cheeks vertical; eye high and situated mid- 

 way between front and hack of head: body tapering forward from the front of the dorsal; 

 head small. 



' H. gc/idiis: not certainly known to occur in Illinois. 



