20 



THE POLAR WORLD. 



ROCKS AND ICE. 



50 (Rensselaer Bay), while the surface temperature was as low as —30°, Kane 

 found at two feet deep a temperature of - S'^, at four feet +2°, and at eight 

 feet -f2G°, or no more than si.v deiji'ecs below the freezing ponit of water. 

 Thus covered by a warm crystal snow mantle, the northern plants pass the long 

 winter in a comparatively mild temperatuie, high enough to maintain their life, 

 while, without, icy blasts — capable of converting mercury into a solid body — 

 howl over the naked wilderness; and as the first snow-falls are more cellular 

 and less condensed than the nearly impalpable powder of winter, Kane justly 

 observes that no " eider-down m the cradle of an infant is tucked in more 

 kindly than the sleeping-dress of winter about the feeble plant-life of the Arc- 

 tic zone." Thanks to this 2)rotection, and to the influence of a sun which f(jr 

 months circles above the horizon, and m favorable localities calls forth the pow- 

 ers of vegetation in an incredibly short time, even "Washington, Grinnell Land, 

 and Spitzl)ergen are able to boast of flowers. Morton jtlucked a crucifer at 

 Caj)e Constitution (80° 45' N. lat.), and, on the banks of Mary Minturn Iviver 

 (78° 52'), Kane came across a flower-growth which, though drearily Arctic in 

 its type, was rich in variety and coloring. Amid festuca and other tufted 

 grasses twinkled the purple lychnis and the white star of the chickvveed ; and, 

 not without its pleasing associations, he recognized a solitary hesj^eris — the 

 Arctic representative of the wall-flowers of home. 



Next to the lichens and mosses, which form the chief vegetation of the 

 treeless zone, the cruciferic, the grasses, the saxifragas, the caryophylla?, and 

 the comi)ositai are the families of plants most largely represented in the barren 

 grounds or tundri. Though vegetation becomes more and more uniform on 

 advancing to the north, yet the number of individual plants does not decrease. 



