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too large for the short summers even with their Arctic heat to 
melt, temper the otherwise unmitigated intensity of a sun that 
shines for the greater part of the twenty-four hours. 
The isotherm of 45° passing through Sitka is the same as that 
of Montreal. The January mean temperature-of 1888 was 30.29, 
and August of the same year 58.4°, the thermometer rising to 
89° and 90° on the hottest days. This mildness and moisture 
comes from the prevailing winds which blow in-shore from the 
warm equatorial current, that turns across the ocean from Japan 
and then sweeps down the coast, giving California its delightful 
climate and making the most magnificent forest belt in the world, 
The trees are few in species, mostly conifers, with a sprinkling of 
cottonwoods, but they are densely crowded and grand in height 
and diameter, their coverts luxuriating in mosses and lichens. 
The long winter, with its abundant congelation, and the short 
summer, effect a snow-line which is comparatively low at Juneau, 
58° north, being about 3,500 feet. This produces a crowding of 
the plants, alpine and sub-alpine, low down upon the mountains, 
particularly where the glaciers descend to the sea. 
In a climb of three thousand feet one passes species found in 
California, Washington, New England, Greenland and Labrador, 
or finds the same species in fruit, flower and bud. Looking 
over the plants of my collection, I note that they fall into four 
classes according to distribution. 
First, those confined to the range of the forest belt; 2.¢., from 
the Aleutian Islands to California, climbing the mountains as they 
descend; such are: 
Gentiana Douglasiana, Bong. 
Vaccinium parvifolium, Smith. 
Romanzoffia Sitchensis, Bong. 
Second, those which follow the mountain ranges southward, 
and extend eastward to the Rocky Mountains: 
Bryanthus glanduliflorus, Gray. 
Castilleia miniata, Dougl. 
Mimulus luteus, Linn. 
Third, those plants whose range is eastward to New England, 
and westward to Japan or Siberia: 
Cornus Canadensis, Linn. 
