18981902. No. 16.] FLOW. PLANTS AND FERNS OF N.-W. GREENLAND. 41 



How it has got there is a somewhat more difficult question to solve. 

 I refer it alternatively to Group A, or Group D. 



Androsace septentrionalis, forming Group III, 4, as absent from 

 Greenland goes to Group A. Group III, 5, contains 3 species, of which 

 one seems to be decidedly american, viz. Potentilla rubricaulis; the 

 two others are more dubious, and so give rise to a question as to 

 whether they should be placed in Group A, or in Group D. Saxifraga 

 flagellaris is spread round the Arctic Regions to Spitsbergen, but its uni- 

 versal appearance throughout Arctic America and the islands, its manner 

 of distribution in Ellesmereland and in N. W. Greenland, make it most 

 probable that it is an american immigrant in Greenland. Pleuropogon 

 Sabinei is spread from Siberia to Novaja Semlja and Franz Joseph 

 Land; but its absence from Spitsbergen, and its range over the Arctic 

 Islands to Ellesmereland, make it probable that it has reached even 

 N. E. Greenland that way. 



The 5 species in Group IV, 1, Campanula rotundifolia, Rhodiola 

 rosea, Juncus castaneus, J, triglumis, Poa alpina, must be reckoned 

 to Group S. In N. E. Greenland alone they are spread into the area here 

 in question, and none of them seems to reach its northernmost part. Even 

 those of them which have an uninterrupted distribution in the south, 

 may, perhaps, have immigrated from both sides, as they are spread both 

 in Europe, including Iceland, and in America. The same is the case 

 with Festuca rubra, which forms Group IV, 2. Carex aquatilis, Group 

 IV, 3, is absent from N. E. Greenland, and its distribution in the north- 

 ern part of Danish Greenland, points to an american origin. I there- 

 fore place it in Group A, notwithstanding that it is not found as yet in 

 N. W. Greenland. 



In Group V, 1, we have the two new Ellesmereland species, the 

 distribution of which is as yet unknown; it is possible that Saxifraga 

 *exaratoides may count as american, Poa evagans must, however, be 

 left out of consideration at present. Taraxacum pumilum (Gr. V, 2) 

 most probably may be reckoned as american. 



Group VI, 1, contains 7 species, all absent from Ellesmereland but 

 found in the five neighbouring districts entered in the table. Among 

 them, Potentilla nivea, Honkenya peploides, and Carex rigida, are 

 rather ubiquitous species that may yet be found in Ellesmereland. 

 I refer them to Group U, together with Salix herbacea, absent from 

 Spitsbergen (but found in Beeren Island and Jan Mayen) and perhaps 

 from the Bering Sea region. Tofieldia palustris and Carex scirpoidea 

 are absent from Western Siberia; Rhododendron lapponicum also from 



