400 THE AMERICAN NATURALIST. (VoL. XXXIII. 
moderate temperature of the air and the prevalence of cloudy 
skies no doubt favor this habit. These northern waters are 
especially rich in the gigantic kelps, so characteristic of the 
Pacific, and the masses of these big brown seaweeds attract 
the attention of the most careless observer. 
After two weeks spent most pleasantly at Sitka, the steamer 
was taken for the return voyage. On the way back we put 
into Glacier Bay, where a morning was spent scrambling over 
the moraine of the great Muir glacier, which fills up the head 
of the bay, and whose sheer cliffs of glittering ice extend for 
more than a mile across it, and rise two or three hundred feet 
above its waters, gray with the detritus of the glacier, from 
which great blocks of ice are constantly falling to add to the 
fleet of icebergs sailing out from the bay into the ocean. For 
many miles back of the ice cliffs the rough surface of the gla- 
cier extended to the bases of the snow-capped peaks, which 
formed the impressive background of this magnificent picture. 
The face of the glacier presented a marvelous variety of color. 
In places the cliffs of ice were pure white, with faint blue veins 
looking like marble, while at other points crags of crystalline 
clearness glittered in the sunlight with all the tints of the 
rainbow. The crevasses were of the purest blue, ranging from 
faint turquoise tints to the deepest sapphire and indigo. Now 
and again a fragment would break off and fall with a thunder- 
ous crash into the bay, where its weight would carry it far 
below the surface, whence it presently emerged with a great 
splash like some huge monster, and presently started ocean- 
ward to join the rest of the iceberg fleet. Most of these float- 
ing ice masses were very free from dirty surface ice, and looked 
like huge blocks of blue-veined marble, or sometimes were 
solid masses of pure blue ice of the most exquisite shades. 
The huge moraine flanking this glacier presented a most 
forbidding appearance, and very little vegetation has succeeded 
in gaining a foothold. Besides a dwarf prostrate willow, a few 
inches high, which was seen in several places, the only other 
plant noticed was an Epilobium, the finest of the genus that I 
have seen. The deep crimson flowers, twice the size of those 
of the common willow-herb, were magnificent: and especially 
