(42) 



General appearance much like that of P. spectahiUs, from which it 

 differs in the scaly cheeks, the more complete lateral line and the greater 

 number of vertical rows of scales. In spectahilis the cheeks are either 

 wholly bare, or a few scales appear behind and below the eye. In asprigenis 

 they are either wholly covered, or naked only on the lower fourth. 

 The vertical rows vary in my specimens of spectahilis from 38 to 43 

 (counting only complete rows), — in asprigenis from 48 to 50. In the former, 

 the lateral line extends over from 25 to 31 scales — in the latter from 34 to 41. 



The head is small and pointed, the eye large, (longer than snout,) the 

 outlines regularly curved, the body compressed and rather deep, the mouth 

 terminal, oblique, and the jaws about even, 



The dorsal fins are sometimes separated by distances varying from 

 the length of half a scale to a scale and a half, but are occasionally quite 

 continuous, the two being united by membrane. 



Length 35 to 45 mm. Depth 4i to 4| in length; head 3f to 4 ; 

 eye in head 3^ to 4 ; nose about f the eye. Width at pectorals 8 to 10 in 

 length ; at middle of second dorsal, 12 to 15. The caudal peduncle is twice 

 long as high. Longitudinal rows |. Breast always naked, opercle wholly as 

 scaly, back wholly scaled before the dorsal, or a narrow strip left bare. 



The first dorsal consists of from 9 to 12 spines. Its height is from 

 ^ to 5 its length, and % the height of the second dorsal. The latter contains 

 from 10 to 12 rays, of which, in one case, the first was a stout sharp spine 

 (XI — 1, 11). Its length is | that of the first, and | greater than that of the 

 anal. The anal consists of two spines and 7 or 8 soft rays, the longest ray 

 reaching to the middle of the caudal peduncle. 14 specimens examined. 

 Taken in small creek near Pekin, 111. 



The naked cheeks and contiguous dorsals are evidently not good gen- 

 eric characters of PcecilicJithys, S. A. F.] 



Genus ETHEOSTOMA, Rafinesque. 



19. ^!;^eostoma/fl6eZ?are Rafinesque. Fan-tailed Darter. (M.V. 227; 

 Poecilichthys Jiahellatus Nelson, 34.) 



In clear waters in the southern part of the state. Specimens 

 from Clear Cr., Union Co., and from Wabash River. 



Var. lineolafum (Agassiz) Jordan. Lined Darter. (M. V. 227 ; 

 Poecilichthys lineolatus Nelson 34.) Clear streams in northern 

 Illinois. Rock River, Ogle Co. Finish. 



20. *Utheostoma squamiceps Jordan. Scaly-headed Darter. (M. V. 

 228.) 



Known only from western Kentucky. 



Genus BOLEICHTHYS, Girard. 



21. Boleichthys eos Jordan & Copeland. Red Sided Darter. (M. V. 

 228 ; Nelson, 34.) 



In clear cold streams throughout the state. Efiingham Co., 

 Johnson Co. 



