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The Agassiz glacier is formed by the union of many high-grade ice-streams on the eastern and nothern slopes of the St. Elias range, and on the southern face of the equally precipitous Augusta range. All of these tributaries have been seen and are indicated in a rough way on the accompanying map.

Seward glacier is the principal feeder of the Malaspina ice sheet. Its most distant tributaries have their sources far to the north of the Augusta range, in the general névé field covering the main mountain mass. Scores, if not hundreds, of secondary glaciers unite to form the trunk stream which is fully three miles broad where best defined, and probably not less than sixty or seventy-five miles long.

Besides the great glaciers enumerated above there are several smaller ice-streams of the same type, such as the Marvine, Hitchcock, Lucia, etc., each of which is eight or ten miles in length and flows through a deep well-defined valley. Between these various trunk streams there are scores of high-grade glaciers that originate in deep cirques in the southern face of the mountains or in some instances, on the rugged slopes themselves where there are no depressions, and descend to and merge with the vast plateau of ice skirting the ocean.

Before giving special attention to the Malaspina glacier it may be well to glance at a few other geographical conditions which influence its existence.

The climate of southern Alaska adjacent to the coast is mild and uniform. The summers are cool with much fog and rain; the winters are not severe, but clear days are rare and snow falls to the depth of several feet. Among the neighboring mountains the snow-fall is excessive and occurs during every month of the year. In the névé region near Mt. St. Elias at an elevation of about 5,000 ft. it is not uncommon to see strata of compact snow without a parting, fifty feet thick exposed in the walls of crevasses. The mean annual temperature on the coast is thought to be about 40-45 deg. F., but this estimate is based on observation at a very limited number of stations. The humidity is excessive, and the mean annual rain-fall