PAPERS BY MEMBERS 1 | 3 



Each of the species of fish most carefully studied favors 

 certain types of streams and certain places in these streams. 

 A. study of the factors that determine these preferences is now 

 being- made, and the results of this work are intended for 

 other publications. Some notes on these habitat preferences 

 are given in this paper in the annotated list and in the table. 



The Charleston region is well adapted for the study of the 

 local distribution of stream fish, for there are many streams 

 present, and these are of a number of different types. They 

 are also located in country of two distinct kinds, prairie and 

 wooded morainal. each of which is typical of that found in 

 large portions of our state. The streams are also interesting 

 because they are along the line, separating the Lower 

 Illinois Glaciation from the AMsconsin Glaciation. These 

 two regions are very distinct ichthyologically. as shown bv 

 the work of Forbes and Richardson. The Coles countv fish 

 fauna is most like that of the Wisconsin Glaciation. 



THE DISAPPEARINXt BEAVER. 

 } '. .:.,*« " ELLIOT R. DOWNING. 



In a bulletin of the State Biological Survey on the ]\ram- 

 mals of Champaign County, the statement was made that in 

 the early days the beaver was an inhabitnant of Illinois. Now. 

 there probably are none of the animals left within the state. 

 It has been my good fortune to follow it in its retreat to 

 regions where it still is abundant. The book that is still tlie 

 American classic on the beaver was written by Morgan, wb.o 

 made most of his observations upon the beaver in northern 

 Michigan. I lived as a boy in the neighborhood of the 

 streams where he saw these animals and have recently had 

 the chance to watch them at work in this same region. ^Nly 

 early interest was one of curiosity merely t my later purpose 

 in studying the work of the animal, to see in how far the 

 skill wiiich he displays is a result of instinct and how far 

 it is a matter of intelligence- Xo other animal leaves such 

 extensive workings and hence the beaver is an exceedingly 

 good subject for the study of animal behavior, since the rec- 

 ord of his work is easily read and relatively permanent. 



Permit me to give a brief resume of the life hibits of the 

 animal as observed in northern Michigan. In the deeper 

 streams where the banks are steep, the beaver does not 

 build the dam. but excavates a burrow in the bank. There 

 are many colonies of these bank beavers in the Upper Penin- 

 sula streams. Usually, however, especially on the srnaller 



