1910 | Heller.—Mammals: Alaska Expedition, 1908. 329 
on favorable slopes, but on the north exposure it appeared to 
reach only 1200 feet. The great bulk of the island is forested, 
the eastern section uniformly by hemlock and spruce. The 
northern slopes in the vicinity of Canoe Passage are about 
equally divided between forest and open tundra areas. This 
variegated nature of the vegetation continues westward alone 
the whole northern slope of the western section. The southern 
exposures of the island appear to be uniformly forested. 
HINCHINBROOK ISLAND. 
The larger part of Hinchinbrook Island consists of two 
parallel mountain ranges. These have a northeast trend, the 
highest peaks attaining an elevation of some 2300 feet. Per- 
manent snowbanks cover the peaks and extend down the northern 
slopes well into the creek valleys. The rock formation of the 
ridges is a hard yellowish quartzite or sandstone. The coast 
formation consists of the usual layers of interlarded slate and 
sandstone, much folded and contorted. The eastern and north- 
ern sides of the island are low and forested. Open tundra is 
less extensive than on Hawkins Island. The country about 
Northeast Bay is low and rolling, with the stream margins well 
forested and the ridges chiefly open tundra. Small lakes are 
numerous. 
GREEN ISLAND. 
Green Island is low and rolling, the island consisting, in its 
northern part at least, of a series of ridges. The rock for- 
mation is largely black sandstone, slate, and conglomerate which 
have been thrown into sharp folds. The tops of these folds 
have been worn away, leaving the harder layers of the vertically 
placed strata in the shape of ridges. The valleys between these 
ridges are quite narrow, dammed where they enter the sea by 
heavy gravel beaches which have backed up the small streams. 
From the ponds thus formed the water escapes by seepage 
through the coarse structure of the dams. The island is well 
forested by rather small trees, interspersed among which are 
many small meadows which make the country easily accessible. 
The island is apparently sinking rapidly along this north shore, 
