The late Mr. W. S. Foster sent me some years ago a list of Lepidoptera taken by himself in 1888 at Marshall Pass, Colorado, which deserves to be put on record as a contribution to the knowledge of alpine entomology. The collecting was done at altitudes from 10,000 to 13,000 feet, on the slopes of the Continental Divide and Mt. Ouray, on the north side of the railroad track. This is in Saguache county, and about forty miles from the district in Custer county, of which the alpine insects are recorded in Can. Entom., 1890.