NOTROPIS 153 



distributed throughout the state in fairly equal ratio, although less 

 abundant in the Illinois, the Kaskaskia, and the Big Muddy than 

 in the other stream systems. It is one of the small number of 

 species which we have found present in the Michigan drainage in 

 larger ratio (1.96) than in any other section. In its continental dis- 

 tribution it is, on" the whole, a northern species, its general area ex- 

 tending from the St. Lawrence and Lake Champlain through the 

 Great Lakes to the northern shore of Lake Superior, the Red River of 

 the North, and the Saskatchewan, and through the Ohio Valley to 

 Tennessee and the Washita River in Kansas, and up the tribu- 

 taries of the Missouri. 



It moves and feeds in large schools, thousands being frequentl}^ 

 seen together near the surface The food of those examined by us 

 (18 specimens, all from the northern part of the state) consisted 

 principally of insects, nearly two thirds of which were terrestrial 

 species, and the remainder chiefly case-worms and larvae of day- 

 flies. Six of the specimens had, indeed, eaten insects only, and 

 these made 90 per cent, of the food of two others. Three taken 

 from Peoria Lake in October had eaten only Entomostraca, which 

 amounted, in fact, to the unusual ratio of 22 per cent, of the food of 

 the whole group. A single specimen had taken about 40 per cent, 

 of its food from the thread algae, and a minute fish had been eaten 

 by another. 



Females greatly distended with eggs and apparently about to 

 spawn have been collected by us from the middle of May to the first 

 of June. The sexual differences are slight, and we have seen no 

 tuberculate males. 



NOTROPIS RUBRIFRONS (Cope) 

 (rosy-faced minnow) ■ 



Cope, 1865, Proc. Ac. Nat. Sci. Phila., 85 (Alburnus). 



G., VII, 255 (Leuciscus) ; J. Sc G., 202 (Minnilus rubrifrons and M. percobromus) ; 

 M. v., 61 (dilectus); J. & E., I., 295; N., 47 (Minnilus) ; J., 60; F., 76 (dinemus, 

 part); L., 18. 



The smaller size, darker and less silvery coloration, shorter and 

 deeper body, longer head, longer snout and maxillary, and smaller eye, 

 as well as the dense tuberculation and flushed color of the head and pre- 

 dorsal region in spring males of this species, will serv^e to distinguish 

 this from the last species described. Length 2f inches; body moderately 

 elongate, back little elevated; caudal peduncle slender, its depth 2 .4 to 

 2 . 8 in its length ; depth in length 4.8 to 5.8. Color of upper parts 

 rather dark olive, the scales dark-edged ; sides silvery above and below the 

 dark, to almost black, lateral band ; a faint and narrow dark vertebral 



