Arctic Plants: Geographical Distribution 91 b 



The lowland, we might perhaps say the "maritime" and "paludine," habit 

 of Juncus is in striking contrast with the sylvan or frequently mountainous habit 

 of Luzula, and wherever arctic elements of the genera meet, such as is only the 

 case in the higher mountains, the species seemingly prove to be of high-northern, 

 i.e. of arctic origin. 



Very few of the Juncaceae are circumpolar, viz. : Juncus biglumis, Luzula 

 spicata, L. hyperborea, and L. parviflora. Nevertheless, six species have been 

 reported from Spitzbergen, from latitudes as high as 78° 30' to 80° 30', 

 and these are : Juncus biglumis, J. triglumis, J. castaneus, Luzula Wahlenbergii, 

 L. hyperborea, and L. nivalis. But we know also from Hart's Report on the 

 Botany of the British Polar-Expedition of 1875-76 (I.e. p. 19), that Juncus 

 biglumis was collected as far north as 82° 27', Luzula arcuata at 81° 49', and L. 

 parviflora at 72° 20'. 



And from the north coast of Siberia (Sibir. Nordkust. Fanerog. Flora) 

 Kjellman has reported: Juncus biglumis, Luzula parviflora, L. Wahlenbergii, L. 

 arctica, and L. arcuata. A similar high latitude is in Greenland reached by 

 Juncus biglumis, 76° 7'; by J. triglumis, J. castaneus, and J. arcticus 70°; and 

 Luzula spicata is reported from 76° 7', andL. parviflora from 72° 20'. 



In the Alps of Switzerland Heer (I.e.) records the following species: Juncus 

 triglumis from an altitude of 8,500 feet, J. arcticus from 8,020 feet, Luzula 

 parviflora from 9,554 feet, and L. spicata from 9,600 feet. On Long's peak in 

 Colorado I collected Juncus biglumis, J. triglumis, and Luzula spicata at an 

 elevation of 12,000 feet, while I did not observe L. parviflora above the timber- 

 line, and never above about 10,300 feet. 



Finally may be mentioned that four of the species collected by the expedi- 

 tion have been recorded from the Altai mountains, and of these Juncus triglumis 

 and Luzula spicata have even reached the Himalayas, where they have been 

 observed at, elevations ranging from twelve to fifteen thousand feet. 



The prevalent arctic-alpine distribution of these Juncaceae may thus 

 indicate either an arctic or an alpine centre. However, the species appear to 

 thrive best in the far north, on the tundra and seashore (Juncus), in the moun- 

 tains (Luzula). And it is a notable fact that such types of Juncus and Luzula 

 as are alpine, but not arctic, are of a habit quite distinct from their arctic con- 

 geners. This may be readily seen when we consider, for instance, the alpine 

 species of Juncus: J. xiphioides, J. Drummondii, and J. Parryi from the Rocky 

 mountains. And with reference to Luzula, the alpine element in Switzerland 

 contains such characteristic types asL. albida„L. nivea,L. Forsteri, L. pilosa, etc. 

 In other words, the two sections Pterodes and Anthelaia of Luzula represent the 

 alpine element, while Gymnodes is mainly arctic. And I believe such distinction 

 in habit in connection with a circumpolar distribution might indicate that these 

 species belong to the arctic flora rather than being of southern, alpine origin. 



According to Bentham and Hooker, the genus Tofieldia contains 14 species, 

 two of which are natives of the Andes, while the others are widely distributed in 

 the boreal and temperate zones of the northern hemisphere. 



Three of the species are of interest to us from a geographical point of view : 

 T. palustris Huds., T. coccinea Richards., and T. calyculata Wahlenb. Having 

 been collected by the expedition, T. palustris is enumerated on Table 1, and the 

 geographical distribution covers part of the polar regions, except Nova Zembla, 

 and we might say also Siberia, since Ledebour credits the species only to Ural 

 (Ruprecht) and Obdorsk (Sujef). Farther south it occurs in the Alps and Pyre- 

 nees, but is absent from Caucasus, the Altai mountains and the Himalayas. 

 On our continent the species is distributed from Labrador to the Aleutian islands, 

 and south to Minnesota. 



T. coccinea is the only species of the genus which Kjellman has credited 

 to the north coast of Siberia; on this continent, John Macoun (Catalogue, I.e.) 

 gives the distribution as follows : Barren ground from lat. 64° to the shores of 



