180 MINNESOTA BOTANICAL STUDIES. 



elsewhere in the region covered in the present paper, partly 

 because well developed there and in part also because there 

 was less else of special interest there to claim attention. Hard 

 woods were sought for these studies, but the influence of coni- 

 fers is seen in the nature of the four species added above for the 

 rough-bark formations of the present region. 



Favorable opportunity for study of the lichens of pine trees 

 was not found till Rainy Lake City was reached. Here the 

 further investigation of the Usnei formation of the pines begun 

 at Red Lake and Bemidji and recorded in the sixth report was 

 continued, as it was thought to be desirable to record the forma- 

 tion from a locality somewhat removed from these two. Here 

 again the usual remarkable similarity was found, and in the 

 formation of conspicuous and well-known lichens, none new to 

 the state or to the formation were found. However, Thelo- 

 schistes chrysopthalmus (L.) Norm, found in both of the other 

 two localities, was wanting and Parmelia saxatilis (L.) Fr. and 

 Pannelia caperata (L.) Ach., doubtless occasionally occurring 

 on the pines at Red Lake and Bemidji, but not considered a 

 conspicuous part of the formation, were at Rainy Lake City, so 

 commonly associated with the other plants of the society that 

 they could not be overlooked as forming a conspicuous portion 

 of it. Again, since it is intended to avoid repetition and make 

 the papers of the series supplement each other as much as pos- 

 sible, it is not thought necessary to reproduce either the list of 

 species or the statement of adaptations as given in the sixth 

 report. 



The next in order is a Cladonia formation, and the one found 

 at Emo is sufficiently different from the similar ones recorded in 

 the fifth and sixth reports for Mankato and Bemidji, so that it 

 seems desirable to give a list of species as follows : 



CLADONIA LICHEN FORMATION OF ROTTEN WOOD (EMO). 



Cladonia fimbriata (L.) FR. var. coniocraea (FLK.) WAINIO. 

 Cladonia gracilis (L.) WILLD. (and two varieties). 

 Cladonia verticillata HOFFM. 



Cladonia pyxidata (L.) FR. var. neglecta (FLK.) MASS. 

 Cladonia pityrea (FLK.) FR. (two varieties). 

 . Cladonia squamosa (Scop.) HOFFM. 

 Cladonia cristatella TUCK. 

 Baeomyces aeruginosus (Scop.) NYL. 



