90 B Canadian Arctic Expedition, 1913-18 



Iceland, and Norway, seems to support the theory, proposed by Nathorst, that 

 the American element in the European mountains may have reached these by 

 way of Greenland during the glacial epoch. 



C. rupestris, not being circumpolar, but represented on our northern coast, 

 in Greenland, Spitzbergen, Scandinavia, Nova Zembla, Iceland, the Alps and 

 Pyrenees, Caucasus, Altai, besides the Rocky mountains, as far south as Colorado, 

 cannot possibly have acquired such wide, but more or less disconnected range, 

 from one single centre, located in the south, or in the north either. 



Carex vaginata is in the table marked down for: islands of the arctic Ameri- 

 can archipelago, arctic Scandinavia, arctic Russia, Iceland, Alps and Pyrenees, 

 and both coasts of Bering strait. The species is, moreover, widely distributed 

 in the mountains of Central Europe; it occurs also in West and East Siberia, in 

 the Amur district, and in northern Japan. Several varieties have been described, 

 viz.: distracta Norman from Finmark, pauciflora (Wahlenb.) Ands. from East 

 Siberia, "Lena," Gruetteri Aschs. et Graeb. from the Baltic provinces, Petersii 

 from Kamtchatka, altocaulis Dew. from Labrador to British Columbia, the 

 northern Atlantic States, and also Michigan and Minnesota. It would thus 

 appear as if the centre of distribution of this species may be located south of 

 the arctic region; the occurrence of certain varieties in the south speaks also in 

 favour of this supposition. 



Furthermore, Carex vaginata is a member of the Grex Cenchrocarpae,^ the 

 species of which are indeed southern types; only a very few have reached the 

 polar regions, viz.: C. bicolor All., C. livida Willd., and C. vaginata. However, 

 the distribution within the arctic region of these species is very limited. 



According to these data, the arctic Gramineae and Cyperaceae do exhibit 

 a much wider distribution in the north than in the south, with only a very few 

 exceptions, namely: Festuca altaica, Elyna, Carex vaginata, C. rupestris, and C. 

 scirpoidea. And, furthermore, there are several members of these families which, 

 according to our present knowledge, are endemic to the arctic regions, viz.: 

 Hierochloe pauciflora, Poa abbreviata, Arctophila, Dupontia, Glyceria, Elymus, 

 Carex stans,C. subspathacea, C. reducta, and C. compacta; in all 12 species (Glyceria 

 with 3), which are confined to these regions and must naturally have developed 

 there. Arctophila and Dupontia are both well marked, and indeed, quite char- 

 acteristic genera, and none of their species are known except from the arctic 

 regions. Furthermore, Hierochloe pauciflora and Poa abbreviata are both excellent 

 species, and may weU be looked upon as genuine arctic types, i.e. "types" with 

 regard to their morphological structure and geographical distribution. 



The species of Glyceria are also interesting from this point of view; their 

 habit is very characteristic, when compared with that of most of the other 

 species of the genus and, as has been shown in the chapter dealing with the mor- 

 phological structure of the arctic plants, G. vilfoidea shows a very singular 

 structure of the stolons, which is almost unique. But with regard to the Cyper- 

 aceae, even if Eriophorum, at least some of the species, may have originated in 

 the arctic, the singular structure of the fruit constitutes no character which the 

 genus does not share with its southern representatives. And among the Carices 

 there seems to be no type especially characteristic of the arctic regions; the 

 genuine arctic species, not only those as are circumpolar, but also those as are 

 confined to the polar regions, resemble their southern allies, alpine as well as 

 lowland types. 



The temperate regions of both Worlds are the principal home of Juncus 

 and Luzula; they have developed there and acquired a habit and structure 

 which marks them wherever they occur. However, there is also an arctic 

 element of both genera which seemingly originated in the far north and of which 

 several types have entered the alpine regions in the south during the glacial 

 epoch; some, but only a few, species are endemic to the arctic regions. 



» Holm, Theo. Greges Caricum. Am. Journ. of So., Vol. 16. New Haven, 1903, p. 458. 



