COLLECTED DURING THE ENGLISH POLA.ll EXPEDITION. 351 



collection. Most of the species growing on them are such as 

 are generally considered muscicolous ; but there are also among 

 them some which elsewhere are wont to appear as saxicolous. 

 This agrees with an observation that I made in Spitzbergen, 

 viz. that a great many of the lichens that grow on wood which 

 has been brought there either by men or by ocean-streams, 

 are the same as those which appear on the surrounding rocks. 

 I think that the reason is the capacity of wood in the arctic 

 regions to resist decay or any sort of destruction. It is, as it were, 

 are perennius ;" and in this respect wood surpasses most sorts 

 of stones, which are split asunder or otherwise destroyed by the 

 joint action of water and frost. 



Some old bones with lichens growing on them have also been 

 collected. It might be supposed that these lichens would be 

 identical with those growing elsewhere on calcareous rocks ; but 

 this is not the case, for almost all of them are muscicolous under 

 normal circumstances. 



Finally, it is my duty to say that, though the number of species 

 enumerated below cannot be thought small when their arctic 

 native country is considered, it does not include all that have 

 been brought home ; for there are some sterile crusts that it is 

 impossible to determine, together with some few apothecia, which 

 I have occasionally found isolated among other species. 



List of the Lichens collected*. 

 :KB.OljETJCA(l£hrb.) T Nyl.,a. rig 



M 



our 



; Alexandra Haven ; Cape Sabine. Always ste- 

 rile ; some specimens from 82° 27' 30'' N. belong to a forma gra- 

 cilenta. Is sometimes so dark that one might easily take it for 

 the next. 



2. Alectoria. nigricans (Ach.), Nyl. 



Westward-Ho! Valley ; winter-quarters of H.M.S. ' Discovery ; 



Alexandra Haven. Sterile. 



Land.— H. W. F." Its length is now about 55 centims. On a transverse sec- 

 tion of about 1-2 eentim. chain., nearly 40 annual circles of very different size 

 have been counted. 



eluded in this list. 



collected 



2c2 



