XXXIX. CONTRIBUTIONS TO A KNOWLEDGE OF 

 THE LICHENS*OF MINNESOTA. VI. 

 LICHENS OF NORTHWEST- 

 ERN MINNESOTA. 



BRUCE FINK. 



CONSIDERATIONS OF DISTRIBUTION AND HABITAT. 



The collections upon which this paper is based were made 

 during the last half of June and all of July, 1900. The region 

 traversed comprises parts of Ottertail, Beltrami and Red lake 

 counties in northwestern Minnesota. This region was not sup- 

 posed, previous to its study, to be a rich field for a lichenist, 

 but because of its relationship to other portions of the state as to 

 lichen flora * it seemed necessary that it should be investigated. 

 Consequently the collection of somewhat more than 200 species 

 as a result of the most extended collecting trip that I have yet 

 made in Minnesota fully met my expectations as to probable 

 results. 



The itinerary was so planned as to include regions furnish- 

 ing the greatest possible variety of substrata, moisture and 

 other conditions calculated to cause variations as to lichen flora. 

 Thus the most southern and western points reached were en- 

 tirely devoid of conifers and possessed an arboreal flora quite 

 similar to that of the southern portion of the state. These areas 

 too were near the border between the wooded region to the east 

 and the prairie to the west. The areas thus briefly character- 

 ized are those about Battle lake and Thief River Falls. The 

 southern portion of the territory traversed, studied at Battle 

 lake and Henning, gave a good view of the high morainic area 

 of the state with its numerous rounded hills covered with granitic 

 bowlders and calcareous soil and pebbles and possessing a scant 

 growth of trees here and there. This southern portion was 



* Fink, B. Contributions to a knowledge of the Lichens of Minnesota. IV. 

 Lichens of the Lake Superior Region. Minnesota Bot. Stud. 2: 234. 29 D. 

 1899. 



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