148 FISHES OF ILLINOIS 



peritoneum dusky to solid brown. Dorsal fin with 8 rays, set usually 

 a little in advance of the ventrals and closer to muzzle than base of caudal ; 

 longest dorsal ray 1 to 1 .3 in head; anal rays 9 or 10, usually 9; pectorals 

 § to f to ventrals, 1 .2 to 1 . 5 in head; ventrals usually not reaching vent. 

 Scales 6, rarely 7, 37-40, 3, rows before dorsal 16 to 25; always much 

 deeper than long on the flanks, becoming exceedingly so in adults; 

 longitudinal rows with an appearance of "running out" behind the dorsal 

 fin; lateral line complete, decurved anteriorly. 



This common, large, and well-known minnow, one of the most 

 conspicuous in our series, is unequally distributed throughout the 

 state, very abundantly so in its northern two thirds. It occurs also 

 in the hill streams of southern Illinois, but is nearly absent from 

 the lower Illinoisan glaciation, whence we have taken it indeed 

 but three times — from two localities on the Little Wabash and from 

 one on the headwaters of the Kaskaskia at the northern boundary 

 of this area. It is especially a minnow of creeks and the smaller 

 rivers — our coefficients for which are 3 and 2.45 respectively — 

 scarcely ever occurring in either lakes or the larger streams. It 

 shows also a marked preference for clear waters, which corresponds 

 to its avoidance of the lower Illinoisan glaciation. Its coefficient of 

 preference for a clean bottom is 2.2. Outside our territory it is re- 

 ported from the entire eastern United States (including the Great 

 Lakes) from the Rocky Mountains to the Atlantic, with the excep- 

 tion of Texas and the southeastern region from the Neuse River on 

 the north to the Alabama on the west. It also ranges into Canada, 

 from New Brunswick and the River St. Lawrence and its tributary 

 streams in Quebec to the Assiniboin in Manitoba. 



Somewhat more than a third of the food of 21 specimens exam- 

 ned by us consisted of vegetable objects, a large percentage of 

 which were alga;, and the greater part of the remainder was insects, 

 both aquatic and terrestrial, the former, however, largely prepon- 

 derant. A single specimen had eaten only fishes. The crustacean 

 ratio was, as usual, insignificant. A single aquatic worm {Lum- 

 briculus) was observed in one. The individuals of this little collec- 

 tion varied widely in respect to the food they had last taken, five, 

 for example, having eaten insects only, while two had eaten little or 

 nothing but alga' and other vegetable objects. 



Its spawning season begins about May 1 and continues to the 

 last of June. Spring males have the top of the head, the tip of the 

 snout, and the predorsal region covered with rather large tubercles. 

 This minnow takes a worm or a grasshopper readily, and is one of 

 the fishes most likely to be found on a boy's string. Although it 



