1907] Fernald,— Soil Preferences of Alpine Plants 173 
distinct incrustations of lime, especially in the sheltered pockets which 
are the hiding-places of Cryptogramma Stelleri. The soils of the 
second primary group of alpine areas are, then, distinctly calcareous; 
and on the calcareous mountains and cliffs we find 135 of the species 
here under consideration,! 94 of which are apparently unknown upon 
the little-caleareous but strongly potassic rocks (Group I) and upon 
the tableland area of Mt. Albert which constitutes Group III. 
This third primary division of our alpine districts, the tableland of 
Mt. Albert, has long been distinguished among the mountains of Gaspé 
as an extensive area of serpentine, a soft rock which is essentially a 
hydrated magnesium silicate. The analysis of typical serpentine as 
given by Dana is ‘‘silica 43.48, magnesia 43.48, water 13.04 = 100," ? 
though extensive areas of massive serpentine do not reach this standard 
of purity. The distinctive soil-element, then, in the third primary 
division of our alpine areas is magnesium. Now, the presence in a 
soil of so large an amount of magnesian compounds and the absence 
of appreciable amounts of potassium and calcium produce conditions 
exceedingly unfavorable to the majority of plants; and the vast ser- 
pentine area of Mt. Albert appears to the unbotanical visitor essentially 
destitute of vegetation. This impression of the area was well described 
by Dr. A. P. Low, the discriminating Director of the Geological Survey 
of Canada, who in the summer of 1883 spent some weeks in a study 
of the geology of the Shickshock Mts. and of Table-top Mt. Mr. 
Low says: “The top of Mt. Albert is nearly flat, and is rent by a deep 
gorge on the east side, which, near its head, splits into several smaller 
ones. The sides of these gorges are quite destitute of vegetation and 
the bare serpentine rocks are weathered to a light buff color. On the 
top of the mountain blocks of serpentine are scattered around, and are 
partially covered by a thick growth of mosses [chiefly Racomitrium 
lanuginosum] and lichens. Sheltered places are occupied by a stunted 
growth of black spruce (Abies nigra), which rarely attains a height of 
ten feet. The branches interlace near the ground and form an im- 
penetrable thicket. The whole surface has a dead appearance, and 
reminds one of the pictures of the moon.” ? 
This vivid impression of the serpentine area of Mt. Albert is gained 
1 In Europe many species have been pointed out as confined primarily to calcareous 
soils. For a bibliography on this subject see Schimper, Pflanzen-Geogr. 129, 130 (1898). 
? Dana, Man. Geol., ed. 4, 68 (1895). 
3 Low, Geol. Surv. Can., Rep. for 1882-83-84, pt. F. 7, 8 (1884). 
