15 



Very abundant throughout the State, occurring in 333 of our collpctlons. In the eastern 

 Wabash basin so abundant as to be a nuisance to the collector. Not so numerous in the 

 largrer streams. 



AA. — Short-intestined Minnows. 

 Semotilus atromactilatus (Mitchill). — Horned Face; Creek Chub. 



A large fat minnow, reaching 10 inches in length. The fine scales on the forward part 

 of the body, the large mouth, and the small barbel on the upper lip near the corner of the 

 mouth, serve usually to distinguish it. It is an active swimmer, feeding on insect larvae, 

 worms, and small fishes. It is provided with a powerful set of pharyngeal teeth. One of 

 our best bait minnows; easily taken in creeks. 



Abundant in streams of smaller size throughout the State. Rarely taken in lakes or 

 sloughs connected with the Illinois River. Oscurs In 149 of our collections. 



Opsoposodus emilia (Hay). 



The validity of this species is frequently questioned. It difl'ers from O. megalovt in 

 the complete lateral line and the black spot on the anterior rays of the dorsal. 



Specimens identified as this species occur in collections from the Illinois River at Havana, 

 the Big and Little Fox rivers in White county, and from Frenck Creek at Gray ville. 



Opsopceodiis megalops (Forbes). (158b) 



A fish with a very small upturned mouth, a black spot on the posterior rays of the dorsal, 

 and an incomplete lateral line. Delicate lines of black mark the edges of the scales. 



Occurs in 67 collections, mainly from the Illinois River and from the streams of south- 

 eastern Illinois. Also found at Urbana and near Galena. Never abundant, but found only 

 sparingly, usually in water of moderate depth with muddy bottom. 



Abramis crysoleucas (Mitchill). — Golden Shiner; Roach; Bream. (159) 



This fish is distinguished from all other minnows by the keel on the belly behind the 

 ventral fins. The body is compressed to a thickness of about one-fifth to one-sixth of the 

 depth. Mouth much upturned; scales large and rounded on their posterior borders: 

 13 rays in anal. 



Found in still water in all parts of the State. Not abundant in collections from the Rock 

 River basin. Occurs in 257 of our collections. 



Cliola vigilax (Baird & Girard). — Fat-head. 



This minnow approaches PimepfcflfZes in the fine scales before the dorsal, in the general 

 form of the body, and in not having the first ray adnate to tbe second of the dorsal, while it 

 differs in having a long intestine and a pale peritoneum. In separating this species from 

 P. notattts we have found that we can usually depend upon the paler color and more ob- 

 tuse head of Cliola. The black spot it the base of the caudal is also usually more distinct 

 than in P. notatus. As in the latter, there is a black spot on the first rays of the dorsal in 

 this species. 



Found in 170 collections, made throughout the State, with the exception of the Lake Michi- 

 gan region. Not abundant in the Rock River basin. 



KIT TO SPECIES OP THE OENUS NOTROPIS FOUND IN ILLINOIS. 



a. Body neither stout nor much compressed; small cylindrical fusiform fishes not 

 more than 2^2 inches in length; depth not more than H of length. 



b. A black stripe around snout, through eye and on side to base of caudal. 



c. No black on lower jaw; chin white N. oatdga. 



cc. Mouth more oblique, lower jaw with some black. 



d. Mouth very small; lower jaw included N. anooknus. 



dd. Mouth large; lower jaw projecting' N. hetehodon. 



bb. Sides without black stripe (dusky or silvery); sometimes dusted on sides and 

 head with black specks. 



e. Fourteen to 17 scales before dorsal. 



f . Anal rays 7 or 8. 



g. Dorsal stripe present; nocaudalspot N. blennius. 



gg. No dorsal stripe. 



h. Dorsal rays 8, anal 8; fins high.' 



hh. Dorsal rays 7, anal 7 N. bctlla. 



r.~ >Care must be taken to avoid confusion of cayuga, afiogenus and htterodon, particu- 

 larly Jitterodon, with Eybognathus nubila. 



»iV. vohieellus; not certainly known to occur in Illinois. 



