152 ohio state; academy of science;. 



Around the margin of the lake is a fringe of trees, the rem- 

 nants of the former general forest, and within this is a series of 

 concentric zones of vegetation which finally disappear in the 

 water, as is usual in such locations. Evidence of rapid filling is 

 present on the west side, where a new series of zones has pro- 

 duced considerable confusion in the centripetal progression. On 

 the east side there is a wide mud flat inside of the shrub zone, 

 which is just now beginning to be invaded by hydrophtic shrubs. 

 The most perfect and primitive arrangement of the vegetation 

 appears at the north end, where a small, low wood-lot has afforded 

 protection from the cultivated field beyond. At the south end 

 the natural conditions have been entirely changed ; here the 

 vegetation has been removed in order to enlarge the available 

 ice-producing surface. The water is thus shallow and some of 

 the zones are either entirely absent or represented only by isolated 

 individuals. There is here also a patch of low woods which lies 

 between the railroad and the lake and formerly the zones were 

 very perfectly developed, as will appear from the photograph 

 taken in 1887 (Fig. 1). 



Glacial lakes are of interest in many ways, but especially 

 because of the rapid changes which must have taken place in 

 comparatively recent times in climate and soil. How far these 

 lakes present similar plant societies as one passes from their 

 southern limits northward is still to be determined. Several 

 glacial lakes have recently been studied in detail, among which 

 may be specially mentioned the "Three Sister Lakes," near 

 Ann Arbor, Mich. 1 



One of the authors of the present paper is quite familiar with 

 the vegetation and surroundings of these " Three Sister Lakes," 

 having often botanized on their banks, and though there are 

 striking similarities in some of the zones, on the whole there are 

 very great differences, as will appear by comparing the reports of 

 Reed and Weld with the description of Brush Lake. That the 

 difference is not primarily due to latitude will be evident from the 

 fact that a number of plants characteristic of the Michigan lake- 

 lets also occur in the Licking Reservoir, about thirty miles east 



1. Reed, Howard S. A .Survey of the Huron River Valley. I. The Ecology of 

 a Glacial Lake. Bot. Gaz. 34: 125-139. 1902 

 Weld, Lewis H. Botanical Survey of the Huron River Valley. II. A Peat 

 Bog and Morainal Lake. Bot. Gaz. 37: 36-52. 1904. 



