12 



Carpiodes difformis Cope. (70) 



Identified In our Illinois River colle'-.tlons. Probably frequently confused with the next 

 species. 



Carptorfes veK^cr (Rafinesque).— Qaillback; Spearfish; Skipjack. (70) 



Known by the excessive elongation of the^rst rays of the dorsal fin. 

 Very abundant everywhere, but almost worthless as food. 



Cycleptus elongatus (Le Sueur). — Black Horse; Missouri Sucker. 



Formerly abundant in the Illinois River, but now only occasionally taken. The single 

 •peclmen taken in our collections of the past three years comes from the mouth of Green 

 River. A specimen was obtained also from the Little Fox River, at Philipstown, 111., in 1882. 



Catostomus commersonii (Lac6p6de). — Common Sucker; Fine-scaled 

 Sucker; Black Sucker. (76) 



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

 varietal forms. 



Abundant; found usually in prairie creeks: not yet taken by us in tributaries of Lake 

 Michigan, Not found in our collections from southward of the latitude of the mouth of the 

 Illinois River, with the exception of one collection from near Mt. Carmel. and (singularly 

 enough) ten collections in the Illinois spur of the Oiarks, in the counties of Williamson, 

 Saline, Hardin, Pope, Johnson, and Union. Taken, in all, from 68 localities. 



Catostomus nigricans (Le Sueur). — Hammer-head; Hog Sucker; Hog 

 Molly; Mullet; Stone-roller. 



A fish of peculiar appearance; head pyramidal, body subconical; eyes very small; 

 mouth large and sucker like. It is a strong swimmer and is chiefly found upon gravelly 

 riffles, where it feeds upon the bottom. As in the case of many other fishes inhabiting simi- ' 

 lar situations, the back is crossed with dark bars, which probably serve as a means of pro- 

 tection against discovery by wading birds and other enemies. 



Abundant in rapid gravelly streams of the Mississippi valley northeastward of a line 

 from the mouth of the Rock River to the mouth of the Embarras River. In this section we 

 have 84 collections of this species, while southwest of this line we have but four, two of 

 these lying very close to the line; viz.. Little Wabash River at Effingham. Spoon River at 

 London Mills. Otter Creek in Jersey county, and Clear Creek. Union county. Not found in 

 the few collections which have been made from streams flowing into Lake Michigan. 



Erimyzon sucetta oblongus (Mitchill). — Chub-sucker: Sweet Sucker. 



The absence of a lateral line serves to distinguish this fish from other suckers. (It should 

 be noted, however, that the young of the next species are without a lateral line also.) The 

 young of this variety are distinguished from adults by the possession of a very black 

 lateral stripe, and may easily be mistaken for minnows. 



This fish is abundant in the Wab&sh basin, in the streams tributary to the Ohio River, 

 and in the headwaters of the Kaskaskia; also fiequently taken at Havana. It is much less 

 abundant tbroughout the Illinois valley, not having been taken by us between the Illinois 

 and Mississippi rivers. It appears in four collections from the Rock River basin. 



Minytrema melanops (Rafinesque). — Spotted Sucker; Black Sucker. 



Readily recognized by the presence of several longitudinal rows of black dots on the 

 scales of the sides. Lateral line absent in the young and incomplete or broken in adults. 



Abundant in the Wabash basin and in the headwaters of the Kaskaskia. One collection 

 from the Saline River at Harrisburg, ^ne from Cedar Creek at Simpson, and one from the 

 Big Muddy at Benton. Rare at Havana and Meredosia and in the northern portion of the 

 State. Not taken between the Illinois and Mississippi rivers. This fish apparently prefers 

 the weedy prairie creeks in situations where it is abundant. 



Moxostoma aureolum (Le Sueur), — Common Red-horse: White "Sucker; 

 Large-scaled Sucker. 



Scales large; body heavy; head larger than in the next, flat between the eyes and squarish 

 in cross-section; nose ending abruptly. 



Very abundant in streams of all sizes northward; generally found in the black-prairie 

 regions. Occurs but six times south of the south line of Shelby county, as follows: Jasper 

 County, N.E.; Fayette County, N.; Wabash County. E.; Wayne County. W. (2); Saline 

 County. S.; and Hardin County, center. 



Moxostoma macrolepidutum (Le Sueur). — Red-horse. 



Scales large; body more elongate than in the last, tapering from before the dorsal fin for- 

 ward; head rather small, rounded, and bluntly pointed. 

 Common in streams of the northern half of the State. 



