SEMOTILUS FALLFISHES 123 



as the headwaters are approached. Within these limits its 

 distribution in Illinois has been quite general, including all our 

 hydrographic divisions except the Michigan drainage and show- 

 ing no marked preponderance in any. Outside this state it 

 ranges far and wide throughout the central and western United 

 States, excepting, however, the Great Lakes and the extreme 

 southern and southwestern part of our area. From the St. 

 Lawrence and its tributaries in Canada, and from New Bruns- 

 wick, Maine, and Vermont, it is found westward and south- 

 ward through the Hudson valley to the Potomac and the 

 Roanoke, through the Ohio and the Mississippi valleys to the 

 Alabama River, and northwestward to Wyoming. 



It is an active swimmer and exceedingly voracious, and with 

 an unusually varied diet for a minnow, including considerable 

 quantities of vegetable food on the one hand, and small fishes on 

 the other. A fourth of the food of twenty-two specimens con- 

 sisted of algae and of miscellaneous vegetable debris. Four of 

 these specimens had eaten little else than filamentous algae, 

 and three had captured small fishes. Grasshoppers, caterpillars, 

 ants, chrysomelid and scarabseid beetles and various other 

 terrestrial insects, together with Corisa, dipterous larvae, and 

 other aquatic forms, were the insects represented, and three of 

 our twenty-two specimens had eaten only crawfishes. 



This species is reported by Jordan to reach a length of a 

 foot, and to be an excellent bait, when df the proper size, for 

 bass, wall-eyed pike, and pickerel. With the possible exception 

 of Hybopsis kentuckiensis, it is decidedly our gamiest minnow. 

 It is always ready to bite at a grasshopper, and will even rise 

 to the fly. It thrives in the aquarium, and with good treat- 

 ment soon becomes so tame as to feed from the hand*. 



Males in full breeding dress have been taken in our May 

 collections. There are, in spring males, two large tubercles on 

 each side of the upper lip just below the nostrils, a row of four 

 other large ones on each side of the eye, a cluster of minute 

 tubercles on the lower part of each opercle, and a row on the 

 margin of most of the scales on the upper part of the caudal 

 peduncle. Reighard has seen a male of this species preparing 

 a nest by excavating the sand and gravel in advance of spawn- 

 ing, but this is abandoned after the eggs have been laid. 



* The eastern chub (Semotilus corporalis) does not occur west of the Alleghanies. It is 

 said by Atkins to spawn in May. It builds great heaps of gravel in running water, but avoids 

 eddies and ripples when spawning. The males build the nest, carrying pebbles in their mouths. 



