[467] 



THE BOTANY OF THE EASTERN COAST OF 

 LAKE HURON. 



BY JOHN GIBSON, B. A., akd JOHN MACOUN, M. A., 

 Professo7^s in Albert College and University, Belleville. 



During the montlis July and August of the past summer, the 

 writers, in company with James Bixrns, Esq., of Bayfield^ made a 

 somewhat satisfactory, though necessarily incomplete exploration of 

 the Botany and Geology of that portion of the eastern coast of Lake 

 Huron lying between the parallels 43° 10' and 44° 50' N. lat. The 

 eastern and western extension of this area embraces only that portion 

 of Western Ontario which is bounded on the west by Lake Huron, 

 and on the east by an imaginary line drawn from the southern bend 

 of the Ptivi^re aux Sables (south), in a direction N. by N. E., to the 

 mouth of the Sydenham River at Owen Sound on the Georgian Bay. 

 The superficial area, therefore, is by no means extensive, but owing 

 to its northern and southern bearing, and its favoured conditions of 

 climate, cannot fail in a botanical point of view to be productive of 

 many interesting facts in the geographical botany of Canada. In 

 treating of the botany of a district so limited in extent as the one 

 under review, it must be borne in mind that, making due allowance 

 for the varying altitude of the country, we cannot with any degree 

 of precision come to any generalizations i-egarding the effect of so 

 limited an increase of latitude upon the vegetation of that particular 

 meridian. We can point, however, to the existence, within this area, 

 of forms whose presence can only be accounted for through a pecu- 

 liarity of causes, geological and climatic ; and on this account it is 

 deemed expedient to preface our botanical notes with a sketch of the 

 more salient points in the physical geology and climatology of the 

 district. 



From Cape Ippewash on the south to the Georgian Bay on the 

 north, the general character of the region is level or gently undu- 

 lating, presenting no conspicuotis highlands with the exception of the 

 bold precipitous escarpments found skirting the southern and south- 

 western coasts of the Georgian Bay. Along the coast of Lake Huron 



