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xXXXIX, 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. 29D. 
1899. 
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