98 FISHES OF ILLINOIS 



themselves adult. Moreover, by their great numbers, by their vari- 

 ous adaptations and correspondingly general ecological distribution, 

 and by their permanently small size, the minnows must distract in 

 great measure the attention of carnivorous fishes from the young of 

 the larger species, upon which, without them, the adults of these 

 larger species would fall with the full force of their voracious appe- 

 tites. By offering themselves, no doubt as unconscious, but suffi- 

 cient substitutes, they thus help to preserve — for their own future 

 destruction, however.be it noticed — the young of many species which 

 would otherwise be forced to feed on each other's progeny. It is 

 not too much to say, consequently, that the number of game fishes 

 which any waters can maintain is largely conditioned upon its per- 

 manent stock of minnows. 



Owing to their abundance in all situations, the number and 

 variety of their species and genera, and the ease with which they 

 may be collected and preserved, minnows are an admirable group 

 for a study of local distribution and ecological relationship, and the 

 data of our collections applicable to such a study have been assem- 

 bled, for convenient inspection and comparison, in the following 

 tables and lists. 



