XVIII. CONTRIBUTIONS TO A KNOWLEDGE OF 



THE LICHENS OF MINNESOTA. IV. LICHENS 



OF THE LAKE SUPERIOR REGION. 



BRUCE FINK. 



CONSIDERATIONS OF DISTRIBUTION AND HABITAT. 



The area treated in this paper includes essentially the counties 

 of Cook and Lake, comprising about 5,000 square miles of land. 

 It lies to the northwest of lake Superior, bordering on the lake 

 for about 150 miles and on the province of Ontario, Canada, for 

 about 125 miles, thus forming the extreme northeastern portion 

 of the State of Minnesota. It was supposed, before studying 

 it, that the region, because of its position, would furnish many 

 lichen species new to the State and to the interior of North 

 America, and the investigation has fulfilled expectations. 

 Besides its geographical position, certain physical features 

 have produced diversity of lichen species as will be shown later. 



The lichens of the region have never been studied previously. 

 Tuckerman, in his Synopsis,* mentions collections from the 

 north shore of lake Superior by John Macoun and L. Agassiz. 

 The collections by Agassiz were made in 1848 and published f 

 from 1850 to 1852. He traversed the north shore from Sault 

 Saint Marie to Fort William. The collecting by Macoun was 

 done in July, 1869, along the north shore in Canada, and in 

 1884 around lake Nipigon. A publication may soon be ex- 

 pected from the latter collector, giving a complete list of the 

 Canadian lichens, and this should add much of interest con- 

 cerning some species listed in this paper. Of the two collec- 

 tors, Agassiz, at Fort William, came within about 50 miles, 

 while Macoun probably came within 150 miles of certain points 



* Tuckerman, E., Synopsis of the North American Lichens, Parts I and II, 

 1882 and 1888. 



f Agassiz, L., Lake Superior, its Physical Character, Vegetation and Animals 

 compared with those of other and similar Regions, pp. 170-174. Boston, 1850. 



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