118 B Canadian Arctic Expedition, 1913-18 



an inflorescence but no green leaves. From a paper which I have pubHshed some 

 years ago,i it will be seen that this species is one of the very few plants that 

 produce root-shoots, and at the same time is stoloniferous. Root-shoots, how- 

 ever, are known from some of the other Pyrolaceae viz. : Moneses uniflora, Pyrola 

 secunda, and P. chlorantha,^ to which may be added P. picta, Chimaphila 

 umbellata, and C. maculata. 



Among the Ericaceae, Ledum, Rhododendron, Loiseleuria, Cassiope, and 

 Arctostaphylos show almost exactly the same distribution in the polar regions, 

 with the exception of Rhododendron being absent from arctic Siberia, and 

 Cassiope being a member of the flora of Spitzbergen. Kalmia, on the other 

 hand, is confined to the American continent. We have thus four circumpolar 

 species represented by this family. "With respect to their distribution farther 

 south, we see from Table 1 that Loiseleuria and Arctostaphylos are the only ones 

 which extend as far south as the Alps and the Pyrenees, and that Ledum is the 

 only one which occurs in the Altai mountains; none have been recorded from 

 Caucasus and none from the Himalayas. With regard to their occurrence in 

 the Rocky mountains, Arctostaphylos, Cassiope, and Rhododendron have been 

 found in the northern range of these mountains while Kalmia extends down to 

 Colorado, and down the Sierra Nevada to California. 



Furthermore may be mentioned that Arctostaphylos alpina is in Greenland 

 distributed as far north as Lat. 70° on the west coast, and 73° 50' on the east 

 coast (Dus^n); that Cassiope tetragona extends to Lat. 79° on the west coast, 

 and 77° on the east coast, besides, as stated above, that it occurs also in Spitz- 

 bergen; Loise^ewna does not extend farther north than Lat. 61° on the east coast 

 of Greenland while on the west coast it extends to Lat. 74° 18'; Rhododendron, 

 on the other hand, reaches the 74th latitude on both coasts; "the variety pro- 

 cumbens of Ledum palustre reaches Lat. 74° in Greenland. This far-northern 

 distribution may indicate that we have some truly arctic types represented 

 by these species, and being besides circumpolar, except Rhododendron, they 

 originated undoubtedly in these regions. 



Otherwise with Kalmia polifolia {K. glauca Ait.) which is more widely 

 distributed much farther south, to Pennsylvania, etc., and of which the forma 

 "microphylla" is the only one represented in the alpine and arctic regions. Thus 

 Kalmia is beyond doubt a southern type, with its centre located in the temperate 

 zone of this continent where it is more or less associated with several other 

 species of the genus. 



While thus the arctic, circumpolar members of the Ericaceae occur with . 

 their typical habit at these high-northern latitudes, the Vacciniaceae V. uligino- 

 jsum and V. Vitis-Idaea appear only as much reduced forms of dwarfed stature 

 .-and with very small leaves; consequently they may not be regarded as arctic 

 types but only as members of the southern flora which accompanied the arctic 

 lon the retreat to the north. V. caespitosum is also a decidedly southern type and 

 jnostly an alpine one, endemic to this continent. 



A very scattered distribution is exhibited by the Primulaceae. Although a 

 distinctly American genus, Dodecatheon has reached the northeastern corner of 

 Asia, "Terra Tschuktchorum," but only the species frigidum, which by several 

 authors is considered a variety of the Atlantic D. Meadia L.; the other species 

 are mainly Calif or nian. 



With respect to Primula, P. borealis is a native of arctic America but has 

 also reached the Asiatic coast of Bering strait; P. striata is quite extensively 

 distributed toward east, namely: Greenland, Scandinavia, Russia, and Nova 

 Zembla, but is absent from the southern mountains. Finally, P. sibirica is 

 known also from Finmark, arctic Siberia, and Altai. 



1 Pyrola aphylla. Bot. Gazette, Vo). XXV. Chicago, 1898. 



2 Irmisch, Th. Bemerkungen ueber einige Pflanzen der deutschen Flora. Flora. Vol. 38. Regensbure 

 1855, p. 628. 



