170 THE CANADIAN NATURALIST. [May 



within the limits of this district many of the characteristic species 

 of the western portions of the States of New York and of Michigan ; 

 and from their relatively lower latitude, and their position near the 

 bend at the head of Lake Erie, we would be as well prepared to 

 find in the townships fronting the Detroit River some of the rarer 

 species of Southern Michigan and Northern Ohio. 



The prairie lands around Lake St. Clair, and extending towards 

 Chatham, indicate the considerably greater breadth of surface of 

 that lake at a recent period (geologically considered). These 

 prairie soils are, very probably, the most recent surface deposits of 

 any extent existing in Canada. Their deposition took place after 

 the waters of the Great Lakes had assumed their present level, 

 and, consequently, subsequent to the formation of the ancient 

 lake ridges, terraces and beaches, so frequently observed in 

 Canada West. They clo not here, however, as in the Western 

 States, occupy extensive tracts of country. At the present day 

 the formation of prairies is in progress along some of our lake 

 shores. On the American side of Lake Erie, the Bay of Sandusky 

 j g — ^ has been well explained by Leo Lesquereux — in process of 

 transformation into prairie land, and on the Canadian side of the 

 same lake, Point Pelee affords an illustration of more recent 

 commencement. 



I am not aware that our Canadian prairies have been explored. 

 There are, however, elsewhere, within the Erie district, some 

 outliers, as it were, of the western prairie flora. Illustrations are 

 found in Vernoiuo fasciaUata Michx., Solidago Ohioensis 

 Riddell, S. Riddellii Frank, SilpMum terebinthinaceum Linn., 

 Hieraeium longipilwm Torrey, and Phlox pllosa Linn. 



Mr. Macoun, more than a year ago, pointed out to me the very 

 interesting fact, that on the Lake Ontario beach at Wellington 

 and Presquile, occur a few plants which, are not to be met with 

 farther inland, and which have been hitherto thought to be limited 

 in range to the more southern districts of Canada, or to New- 

 York, Ohio, and other of the middle States. The more interest- 

 ing species which he has thus far detected are Jeffersonia dipliylla 

 Pers., Lithospermum Mrtum Lehm., Rkynchospora capillacea 

 Torrey, Sderia verticillata Mnhl., Sporobolus cryptandrus Gray, 

 Pafticum virgatum Linn., and Hypnum trifariwm Web. and 

 Mohr. Upon these beaches the same discerning botanist has 

 obtained Cladium mariscoides Torrey, and Scirpus p mciflorus 

 Smith, neither of which have been hitherto familiar as Canadian 



