Marshall, 1939 Otus flammeolus Trail from Tenaya Lake to Mirror Lake (10.9 mi long), Yosemite Nat. Park, Mariposa Co. Calif. July 20, 1939 No moon, clear, calm at dusk. Begun working forest in flat country around S part Tenaya lake for O.f. Almost pure lodge-pole pine in dense stands surrounding granite areas or meadows. Not far below subalpine forest of mt hemlock etc. But above typical Canadian zone Jeffrey pine & red fir. Spent about 3 hrs - no results. Finally arrived at an open grove of red fir on a slope after crossing a lot of granite country. Now about 1/3 mi. down trail. Red fir, W. white pine & lodgepoles(?) around a pond. Open forest of large trees. Exposed slope (not a deep canyon). A or calling when arrived. May have started when heard my boots further up trail.