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 - 8°, at four feet +2°, and at eight 

 feet +26°, or no more than six degrees below the freezing-point of water. 

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

 Avinter in a comparatively mild temperature, 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 in 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 protection, and to the influence of a sun which for 

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

 ers of vegetatioi* in an incredibly short time, even Washington, Grinnell Land, 

 and Spitzbergen are able to boast of flowers. Morton plucked a crucifer at 

 Cape Constitution (80° 45' N. lat.), and, on the banks of Mary Minturn River 

 (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 chickweed ; and, 

 not without its pleasing associations, he recognized a solitary hesperis — 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 cruciferre, the grasses, the saxifragas, the caryophyllte, and 

 the compositae 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. 



