CHAP. V.] ARCTIC FLORA. 69 



lichens specifically identical with those of Northern Europe. 

 Among these, we saw on the rocks the Parmelia centrifuga, a 

 lichen common in Sweden, but not yet met with in Great Britain, 

 of a greenish-white color, which, commencing its growth from a 

 point, gradually spreads on all sides, and deserts the central space. 

 It then assumes an annular form, and its reddish-brown shields 

 of fructification, scattered over the margin, remind one, though 

 on a miniature scale, of those &quot; fairy rings&quot; on our English lawns, 

 which appear to be unknown in America, and where fungi, or 

 mushrooms are seen growing in a circle. 



The flora of the uppermost region of Mount Washington con 

 sists of species which are natives of the cold climate of Labrador, 

 Lapland, Greenland, and Siberia ; and are impatient, says Bige- 

 low, of drought, as well as of both extremes of heat and cold ; 

 they are therefore not at all fitted to flourish in the ordinary 

 climate of New England. But they are preserved here, during 

 winter, from injury, by a great depth of snow, and the air in 

 summer never attains, at this elevation, too high a temperature, 

 while the ground below is always cool. When the snow melts, 

 they shoot up instantly with vigor proportioned to the length of 

 time they have been dormant, rapidly unfold their flowers, and 

 mature their fruits, and run through the whole course of their 

 vegetation in a few weeks, irrigated by clouds and mist. 



Among other Alpine plants, we gathered on the summit 

 Menziesia cerulea, and Rhododendron laponicum, both out of 

 flower ; and not far below, Azalea procumbens. Mr. Oakes 

 pointed out to me, in a rent several hundred feet above the lower 

 margin of the bald region, a spruce fir growing in the cleft of a 

 rock, where it was sheltered from the winds, clearly showing 

 that the sudden cessation of the trees does not arise from mere 

 intensity of cold. We found no snow on the summit, but the 

 air was piercing, and for a time we were enveloped in a cloud 

 of dense white fog, which, sailing past us, suddenly disclosed a 

 most brilliant picture. On the slope of the mountain below us, 

 were seen woods warmly colored with their autumnal tints, and 

 lighted up by a bright sun ; and in the distance a vast plain, 

 stretching eastward to Portland, with many silver lakes, and 



