186 ILLINOIS STATE ACADEMY OF SCIENCE 



ECOLOGICAL SUEVEY OF THE FAUNA OF 

 LAKE KNOX 



Florence Adcock, Knox College 



I. Description of the Lake. 

 II, Reasons for choosing this particular region for our 

 ecological survey. 



III. Purpose in the work to make as extensive a survey 



as possible, in the limited time, af the fauna of 

 the lake and the conditions affecting the life of 

 the lake. 



IV. Methods. 

 V. Ecology. 



VI. General Survey of the Fauna with ecological notes. 



Lake Knox is a small, artificial lake or pond almost 

 triangular in shape ; and is 380 feet long, 210 feet wide at 

 the wider end and 90 feet wide at the other. It lies in 

 an east and west direction and is situated beside the 

 Sante Fe railroad track two and a half miles east of 

 Galesburg, Knox County, Illinois. The lake, which is 

 750 feet above sea level, is artificial and dates back to 

 about 1880, when it was made by Purington Brick Com- 

 pany to supply water for their brick works. The pond 

 is very shallow, being about eight or ten feet deep; but 

 there is a seasonal change of several feet due to spring 

 rains and summer drought. The water supply is largely 

 surface water which drains in after rains. Two springs 

 also contribute to the water of the pond; of these one 

 empties directly through a pipe from a well just a few 

 feet south of the railroad track, midway on the south 

 side; while the other, which is about one-quarter mile 

 south of the lake, drains into it through a creek and an- 

 other pond. The stream enters the pond at the south- 

 east corner. The lake is drained by a large pipe running 

 under the street car track 75 feet from the east end of the 

 north side and by a small pipe under the south end of the 

 east embankment. 



The banks of the pond are partly of bricks and cinders, 

 especially the south bank where the railroad company 



