82 B 



Canadian Arctic Expedition, 1913-18 



centre of these species, their centre of development and of distrijjution. For this 

 purpose I have especially selected such species as are not circumpolar, and of 

 which the distribution in the south is well exemplified. 



In beginning with the Pteridophyta, the species collected by the expedition 

 are too few to give us any idea of the representation of this group of plants in 

 the arctic region. Therefore, in the accompanying table (Table 2), I have 

 enumerated all the species known from our arctic shore, including the islands of 

 the archipelago, and from Greenland; however, in view of the fact that several 

 species reported from Greenland have not, so far, been found on our arctic 

 shore, a special column has been given to the species known from that country. 

 On the other hand, no column has been given to arctic Siberia, since, according 

 to Ledebour (Fl. Rossica I.e.), Dryopteris fragrans is the only fern recorded from 



