118 FISHES OF ILLINOIS 



in which level of upper lip is scarcely above that of lower margin of orbit; 

 maxillary a little longer than eye, reaching very little past anterior nostril, 

 3.5 to 4.5 in head: jaws about equal; isthmus comparatively broad, its width 

 greater than diameter of eye. Teeth 4-4 or 4-5; intestine 2 to 3 times the 

 length of head and body; peritoneum black. Dorsal fin I,* 8, low, placed 

 directly over ventrals and a little farther from muzzle than base of caudal; 

 longest dorsal ray 1.2 to 1.6 in head, usually greater than 1.4, anal rays 

 I,* 7; pectorals % to ventrals, 1.2 to 1.5 in head; ventrals past front of anal 

 in males, scarcely reaching vent in females. Scales 8 or 9, 42-48, 5 or 6, 

 much crowded in front of dorsal fin, before which there are about 25-30 

 rows; lateral line incomplete, sometimes almost wanting; when present, with 

 a noticeable downward curve anteriorly. 



This species has a general range from the northeast to the 

 southwest, but is not reported from the southeastern part of the 

 United States. It occurs throughout the Great Lake basin to 

 Lake Champlain, throughout the Ohio basin and up the Missis- 

 sippi to the headwaters of the Missouri, and thence northward 

 to the Red River of the North and the Saskatchewan, and 

 southwest to the Rio Grande. Its distribution in Illinois is a 

 miniature copy of its general range, being limited to the northern 

 and western three fourths of the state, leaving the southeastern 

 part with no representation of this species in our collections. 

 It is, in fact, one of the fishes already frequently mentioned, 

 which are practically limited to the Mississippi drainage in this 

 state, and occurs in our collections from the tributaries of the 

 Ohio only from one group of four localities on the headwaters of 

 the Embarras where these approach most closely to the upper 

 tributaries of the Kaskaskia. Notwithstanding the general 

 exclusion of a large part of southern Illinois from its range, it 

 enters the lower Illinoisan glaciation in the branches of the 

 Kaskaskia. It frequents muddy waters freely, occurring there, 

 indeed, in disproportionate frequency, our ninety-five collections 

 of the species giving us a frequency coefficient of 2.08. Like 

 most of our minnows, it is relatively more abundant in creeks 

 than in other waters (coefficient 2.68) and, next to these, in the 

 smaller rivers (1.82). It is fairly well represented, however, in 

 rivers of the first class (.85), and occurs not infrequently in low- 

 land lakes and ponds (.23). It has not been taken by us from 

 our northeastern lakes of glacial orgin nor from Lake Michigan 

 or from the drainage of its basin. 



We have found it commonest in the short muddy creeks con- 

 nected with the larger rivers, and especially abundant in the 



* See key to genera of Cyprinidce. 



