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C. Flora of Eagle Lake and Vicinity. 

 H. Walton Clark. 



The work riiilxMiicd in the foHowin.y- report was accomplished liy the 

 writer, assisted by Mr. Charles :m. Ek, diiriiig the suiuirers of 1899 and 

 lOilO. under the anspit-es of the Indiana I'niversity Biological Station. The 

 purpose of the work is to present a study of Eagle Lake as a unit of 

 en\ ironnient as regards plant life, and the special line of investigation 

 was that of the various plant aggregates of the lake, including their rela- 

 tions to each other and to that body of water. Many thanks are due to 

 Dr. C. H. Eigenmann. Director of the Station, and to Dr. Mottier. Head 

 of Department of Botany of the the Station, for assistance in suggesting 

 and mapping out lines of work. 



As regards the ytlan of the work, it will be helpful to the reader to bear 

 in mind that the survey of the area studied was made in a series of eon- 

 centric rings, beginning at the northeast corner of the region descrllied. 

 that is, at the laboratories, and starting southward. All descriptions have 

 this beginning and sequence, and the sides of the lake are described in the 

 following order: (1) east side. (2) south side. (3) west side. (4) north side. 

 Eagle Lake is one of the many small lakes of northei-n Indiana which 

 occupy depressions in the surface of the glacial drift. It is somewhat 

 irregular in outline, and consists of a large main I)ody, a somewhat narrow 

 neck or channel, and a large bay at the west end. According to Mr. 

 Large, who made a survey of the lake several years ago (Proceedings Ind. 

 Acad. Sci., 1890), the area of the lake is about 0.807 square mile. 



Before entering into a detailed description of the lake and its flora, 

 however, it may lie well to consider briefl.v the surrounding country. 

 This description of the region surrounding the lake is not intended to be 

 exhaustive; it is simply presented as a sort of frame for the picture of 

 the lake itself. The whole region from the lake shore to and including 

 characteristic poi-tions of the high ground beyond the limits of the lake 

 plain, moreover, rot only represents a sort of unit area in itself, but at 

 the same time includes an interesting variety of conditions and furnishes 

 interesting Ints of well marked biological areas that are to be found on a 

 large scale elsewhere, but whicli liere in tlieir limited size offer veiy favor- 

 able opportunities f(n' study. 



Eagle Lake and its plain are nearly surrounded by a ratner abrupt 

 terrace of yellow sand, which rises at varying distances from the lake 



