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the forest-covered area still nearer the outer margin of the glacier. Large quantities of trees and bushes fall into them with the debris that slides from their sides, and tree trunks, roots and soil, thus become buried in the moraines.

Forests on the moraines.—The outer and consequently older portions of the fringing moraines are covered with vegetation, which in places, particularly near the outer margin of the belt, has all the characteristics of old forests. It consists principally of spruce, alder and cottonwood trees, and a great variety of shrubs, bushes and ferns. In many places the ice beneath the dense forest is not less than a thousand feet thick. The vegetation is confined principally to the border of the Seward lobe. Near Yahtse river the belt is 5 miles broad, but decreases toward the east, and is absent at the Sitkagi bluffs, where the glacier is being eaten away by the sea. It is only on the stagnant borders of the ice sheet that forests occur. Both glacial lakelets and forests on the moraines are absent where the ice has motion. The forest-covered portion is by estimate between 20 and 25 square miles in area.

Outer margin.—The southern margin of Malaspina glacier, between the Yahtse and Point Manby, is abrupt and forms a bluff that varies in height from 140 to 300 feet or more. The bluff is so steep in most places and is so heavily incumbered with fallen trees and boulders, that it is with difficulty one can climb it. Many times the trouble in ascending is increased by land slides which have piled the superficial material in confused heaps, and in other instances the melting of the ice beneath the vegetation has left concealed pit-falls into which one may drop without warning. The bluff formed by the margin of the glacier when not washed by the sea, is boldest and steepest where the covering of vegetation is most dense. Where the covering consists of stones and dirt without vegetation, however, the margin may still be bold. This is illustrated between the mouth of the Yahtse and Icy cape, where the ice is concealed beneath a general sheet of debris, but has a bold convex margin which rises abruptly from the desolate torrent-swept waste at its base.