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VI. A New Arrangement of the Genus Polytrjfhum, with fame Emen- 

 dations. By Mr. Archibald Menzies, F. L, S. 



Read February 7, and March 7, 1797. 





IT is not my intention to prefent you with a long and tedious 

 hiftory of the genus Polytrichum \ my obje&s are merely to efta- 

 blifli, by your fanction, what I conceive to be its true and obvious 

 charafteriftics, and to difcriminate the different fpecies, by laying 

 before you, with due diffidence, the following arrangement, in 

 which you will readily perceive that I have added feveral new ones, 

 and feparated fome of the moft confpicuous varieties of authors 

 into diftinct fpecies. This led me on to form new defcriptions, 

 and to new-model the whole genus. 



At the time this genus was firft defcribed, there were but few 

 fpecies of it known ; confequently its chara&er could not be made fo 

 general, nor its arrangement fo complete, as when a much greater 

 number of fpecies are at once before us. Indeed it is pretty evident 

 that Linnaeus took its character chiefly from the Polytrichum com- 

 mune and what were confidered as its varieties, as we find fo much 

 ftrefs laid upon the apophyfis at the bafe of the capfule, that, for 

 want of that angle diftinction, three fpecies were then excluded, 

 and forced with difcordant characteriftics into another genus, un- 

 der the name of Mnium Poly trie boides, and varieties : and although 

 fome of thefe have been fince reftored to their proper place, on ac- 

 count of their natural affinity, yet we find but few fatisfa&ory at- 

 tempts 



