27 



cc. Dorsal spines 11 or 12. 



d. Nape scaled: no red or green marklnera; sides with 8 or 9 quadrate black spots. 



H. OUACHITAB. 



dd. Nape naked; coloration brilliant in life, variously yellowish, black, erreen. 

 bronze, and rust-red; 7 dark bars extending from lower part of side over back 

 and down opposite side H. kvides. 



bb. Gill membranes broadly connected across isthmus; margin of preopercle serrate. 



U. 8CIEBCS. 



Uadropterus phoxocephalus (Nelson). (341) 



Form slender; head pointed; mouth nearly terminal; sides with quadrate or diamond- 

 shaped dark blotches, smaller than in ^. aspro. sometimes grading: into bands; back also 

 blotched or banded with dark; spinous dorsal with a band of orange-red. 



Taken from 77 localities, distributed throughout Illinois; usually found in the rapids o£ 

 large creeks or rivers; rare in southern Illinois. 



Hadropterus aspro (Cope & Jordan), — Blacfc-sided Darter. (340) 



Sides marked with large black spots. The gill membranes rather narrowly joined 

 across the isthmui*, orerlappins; or merely joining at the front, all gradations between 

 these conditions occurring. The edges of the preopercle not serrate; premaxillary not pro- 

 tractile; mouth large and terminal. 



In rapid streams in all parts of the State. 

 Hadropterus evides (Jordan & Copeland), (343) 



A few specimens from Rock River in Ogle county, 1877. 



Hadropterus scierus Swain. (342) 



Differing distinctly from fl". aspro in the serration of the preopercle and in the broader 

 connection of the gill membranes across the isthmus. 



One specimen taken from Skillet^ Fork, in Wajne_county. Several others referred to 

 this species are possibly only v'arreties of MTH^S^ro. 



Cottogaster uranidea (Jordan & Gilbert). 



Not identified in our collections, but reported from the lower Wabash basin, in Indiana, 

 by Dr. Evermann. 



Cottogaster copelandi [J ordsLTa) . (336) 



Occurs throughout central Indiana in clear brooks. 



Cottogaster shumardi (Girard). (336) 



With much the apearance of the black-sided darters (genus ffadropterus). froTa which it 

 is separated by the protractile premaxillary. Males with a very deep and long anal fln, 

 which reaches beyond the base of the caudal in some instances. 



Not common in Illinois. Found in the Wabash River in Wabash county, in the Kaskaskia 

 River at Carlyle and Cowden, twice in the Illinois River, near Meredosia, and fiive times at 

 Havana. 



Diplesion blennioides (Rafinesque). — Green-sided Darter. (332) 



A large darter, with much decurved profile, small mouth, and large fins; with prominent 

 green markings. One of the handsomest of our darters. 



Confined to the Wabash basin, where it is abundant in the streams of Champaign and 

 Vermilion counties, less abundant in the Embarras River and its tributaries, and present 

 in one collection from the Little Wabash Kiver in Clay county. Occurs in 25 of our col- 

 lections. 



Boleosoma nigrum (Rafinesque). — Johnny Darter. (325-326) 



An inconspicuous little fish; the body slender and of pale straw-color, sprinkled with 

 brown dots or W-shaped marks. 



The Johnny darter lives in almost all situations, but is most commonly found on sandy 

 bottoms. Abundant throughout the State in all our streams and lakes. Taken in 282 of our 

 collections. 



Boleosoma camurum Forbes. (330) 



Differs from £. 7iiariim In the more slender body, longer caudal peduncle, and Incomplete 

 lateral line. 



