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Mycologia 



ally rimulose, often abundantly ruptured with white soralia; 

 primary branches flexuous, dichotomous, divaricate, axils occa- 

 sionally compressed (max. length 12 cm.) ; secondary branches 

 dichotomous ; fibrils short. Apothecia unobserved. 



Contingent phases: (a) yellowish-brown, (b) proximal 

 portions black. 



Substrata : On living and dead trees, on old fence rails, and 

 occasionally on moss and humus covered rocks. 



Geographical distribution : Common throughout the Transi- 

 tion and Boreal zones, occurring sparingly in the upper Austral. 

 It is recorded from Oregon (Roell), British Columbia (Macoun) 

 to Alaska (Cummings) in the west, and occurs from Virginia and 

 Maryland to Labrador (Eckfeldt) in the east. It occurs in the 

 middle states from Iowa, Illinois (Fink), and Minnesota (Fink) 

 northward to Great Bear lake (Richardson, Leighton) and 

 Greenland (Vahl, Macoun). It is also found commonly in the 

 Boreal swamps of the upper Austral zone. 



Observations : This plant, which, according to Crombie has 

 never been found bearing apothecia,* is distinguished by its wiry, 

 rigid thallus. Its branches in most specimens are spinulose and 

 largely ruptured with white soralia. Though I have examined a 

 great many specimens I have never seen a fertile plant, yet Tuck- 

 erman records it as follows : " White Mountain, fertile, Lesque- 

 reux; as also on branches of firs in cold swamps, where equally 

 fertile " ; Dr. Farlow informs me, however, that at present no fer- 

 tile specimen is in the Tuckerman herbarium collected by Lesque- 

 reux. It has been argued (Fink) that in the absence of apothecia 

 it should be kept as a variety of jubata, and if it had not already 

 been raised be Gray, Nylander, Wainio, and Norrlin to specific 

 rank I would hesitate to do so. The generally caespitose and 

 wiry thallus seem sufficient grounds for recognizing it as a species, 

 for it certainly shows little intergradation with the pliant and 

 pendulous jubata or the more lax and pendulous implexa. It does 

 not seem likely that jubata is another condition of growth of this 

 same plant, but rather more probable that it is not as yet known 

 in a fertile state. To grant this, however, we must believe such an 

 experienced and careful a worker as Tuckerman at fault. 



* Lightfoot, Fl. Scot. 892. 1777, records it fruited. 



