248 MINNESOTA BOTANICAL STUDIES. 



colored below. No. 173 yielded spores of the usual size meas- 



urincr ^— ^ mic. and much constricted in the middle. No. 374 

 ^ 18-23 ^ 



gave spores only mic. and scarcely constricted. 



48. Physcia pulverulenta (Schreb.) Nyl. var. leucoleiptes 

 Tuck. 



On rocks and trees, probably rare. Sterile. Grand Portage 

 island, June 23, 1897, no. 119. Misquah hills, July 5, 1897, 

 no. 496. Snowbank lake area, July 27, 1897, no. 966. Thal- 

 lus black below. 



Not previously reported from Minnesota. 



49. Physcia stellaris (L.) Tuck. 



On trees and rocks, frequent or infrequent. Grand Portage 

 island, June 23, 1897, nos. 105 and 142. Gunflint, June 30, 

 1897, no. 283a, and/ July 2, 1897, no. 394. Misquah hills, 

 July 5, 1897, no. 460. Tofte (Carlton peak), July 10, 1897, 

 no. 570. Beaver Bay, July 13, 1897, no. 700. Two Harbors, 

 July 17, 1897, no. 801. Ely, July 28, 1897, no. 1012. 



Occasionally the tree forms show dark fibrils and even dark 

 thallus below so that the rock growing variety, below, could 

 only be distinguished certainly by the crenulate border of the 

 apothecia. The plant is much more variable than farther south 

 in Minnesota and Iowa. No. 570 yielded apothecia that were 

 somewhat ciliate below, but the plant is white below and other- 

 wise like the present plant rather than P. obscura (Ehr.) Nyl. 



50. Physcia stellaris (L) Tuck. var. apiola Nyl. 



On rocks, frequent or infrequent. Grand Portage island, 

 June 21, 1897, no. 108. Gunflint, June 30, 1897, no. 284. 

 Misquah hills, July 5, 1897, no. 469. Tofte, July 12, 1897, 

 nos. 640a and 641. Beaver Bay, July 13, 1897, no. 704. 

 Snowbank lake area, July 26, 1897, no. 953. 



51. Physcia tribacia (Acii.) Tuck. 



On rocks, rare and sterile. Grand Portage, June 23, 1897, 

 no. 92. Misquah hills, July 5, 1897, no. 449. Snowbank 

 lake area, July 20, 1897, no. 847. 



52. Physcia hispida (Sciireh. Fr.) Tuck. 



On trees, locally infrequent and poorly fruited. Grand Port- 

 age island, June 21, 1897, no. 63. 



