134 FISHES OF ILLINOIS 



NOTROPIS CAYUGA ATROCAUDALIS Evermann 



Evermann, 1891, Bull. U. S. Fish Comm., XI, 76. 



Length 2h inches; body comparatively shorter and deeper than in the 

 last species, the depth 4 to 4 . 6 in the length ; caudal peduncle slender, its 

 depth 2.2 to 2 . 7 in its length. Color as in the last, except that the dark 

 lateral stripe is solid, there being no transverse crescentic bars at bases 

 of scales of lateral line. Head short, 3.8 to 4.2, its width 1 . 7 to 1 .9 in 

 its length ; interorbital space 2.6 to 3.1; eye 2.8 to 3.3; nose 3 to 3.7; 

 mouth very small, but relatively larger than in the last species, the max- 

 illary 3.6 to 4.3 (average 3.83 for 10 specimens). Teeth, intestine, and 

 peritoneum as in last species. Dorsal fin with 8 rays, inserted distinctly 

 in front of ventrals and closer to the muzzle than to the base of the 

 caudal. Scales 5, 33-38, 3 or 4; 12 to 14 before dorsal; lateral line 

 sometimes wanting on a few scales. 



Females distended with eggs taken in June; snout, cheeks, chin, and 

 top of head of breeding males quite thickly covered with evident though 

 small tubercles. (Tubercles not observed in males of N. cayuga.) 



We have ten collections of this minnow, containing thirteen 

 specimens from the Illinois and adjacent waters, near Meredosia, 

 and one from the main river at Havana. A specimen from Mack- 

 inaw creek in Woodford county, one from Anderson's branch, in 

 Union county, and one from the Little Fox River at Phillipstown 

 may be referred with some uncertainty to this variety. Specimens 

 taken at Greenway, Arkansas, by Dr. Meek are, without much 

 question, identical with the form here described. The uncertainty 

 arises from the difference between the published figure of N. cayuga 

 atrocaudalis and the specific description, the figure showing the 

 lateral stripe solid and the dorsal fin inserted in front of the ven- 

 trals, and the description stating that the dorsal is slightly behind 

 the ventrals. 



NOTROPIS HETERODON (Cope) 



Cope, 1S64, Proc. Ac. Nat. Sci. Phila., 2S1 (Alburnops). 



G., VII, 261 (Leuciscus); ]. & G , 163 (Hemitremia) ; M V., 55; I. & E., I, 261; N., 

 47 (Hemitremia); J. 62 (Hemitremia); F. F., I. 6, 85 (Hemitremia); F., 78; L., 16. 



This small species, distinguished from N. anogenus by its larger and 

 less oblique mouth and pale peritoneum, agrees with it in the general 

 form of its body and in having a dark lateral stripe from the tip of the 

 snout to the base of the caudal. It is sharply enough separated from 

 N. cayuga by its larger mouth and black-tipped chin. Care is sometimes 

 required to separate it from H ybognathus nubila, although that species 

 differs from it radically in its generic characters. Length 2 inches; 

 body moderately compressed and back as a rule noticeably elevated 

 in adults; depth 4.1 to 4.6 in length; caudal peduncle slender, its 



