134 FISHES OF ILLINOIS 



NOTROPLS CAYUGA ATROCAUDALIS Evermann 



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



Length 23/9 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 maxillary 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 Ilhnois and adjacent waters, near Meredosia, 

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

 Mackinaw 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 ventrals, and the description 

 stating that the dorsal is slightly behind the ventrals. 



NOTROPIS HETERODON (Cope) 



(Map XXXIV) 



Cope, 1864, Proc. Ac. Nat. Sci. Phila., 281 (Alburnops). 



G., VII, 261 (Leuciscus); J. & G., 163 (Hemitremia) ; M. V., 55; J. & 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 Hybognathus 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 depth 2.3 to 3 in its length. Color olivaceous, rather 



