IN the front range of the Rocky Mountains of Colorado are several remnants of glaciers. One of these, the Arapahoe glacier, has an area at present of about one-half square mile. It lies on the eastern slope of the continental divide, twenty-one miles due west from the city of Boulder. It is inclosed by nearly vertical walls five to seven hundred feet in height, forming a deep cirque opening to the east. The valley leading eastward is that of a branch of North Boulder Creek. This valley has been occupied by a glacier to a distance of at least eight miles to the east. The bottom of the valley for four miles eastward from the present glacier is occupied by a series of lakes resulting from the glacial action and the intervening topography is marked by roche moutonees (Fig. I). The front of the glacier has retreated up this valley to its present position, and its length has been thereby reduced from nine miles to one mile. The features of this glacier at the close of the summer of 1902 have a peculiar interest. The snowfall for the past three winters has been deficient, and the melting in the ensuing summers has been excessive. The results of these climatic circumstances appear in a great contraction of the ice-covered area, an unusual exposure of fresh moraines and, what is still more important, an almost complete absence of snow below the neve. This last condition is responsible for many fine exposures revealing the stratification of the ice, and for the complete uncovering of crevasses, some of which stand open as much as ten feet. Moraines.-The bottom of the valley is far from being a single trough, and the glacier is therefore by no means a single