K Dixon 1949 Microthera whitneyi Apr. 20 Cassadora Spring, 23 mi. ENE Globe, 4050 ft., Gila Co., Ariz. (Account written up April 21). Heard calls of this species in riparian trees (cottonwood, walnut, sycamore, hackberry, willow) after darkness had set in. Calls high-pitched (not recorded at time); one a long series of notes. Another a single whistled note reminiscent of Stellar Jay "whistle". F.A. Pletka and I paid particular attention to one bird which moved about in hackberry trees shifting perch frequently and calling, often using the whistle and another type of note but never the long series as described in Peters's guide. On at least one occasion another owl flew into the tree and the first shifted perch simultaneously. Once when I imitated the whistled note, I saw the owl on a branch directly overhead peering down at me. As I fumbled about shifting loads the owl flew on. Eventually I collected one owl which Pletka saw silhouetted. This bird was a ♀ in breeding condition although we had thought it to be a juvenile because of its unsusppecting behavior. Russell Pletka collected a ♂ in the same tree a few minutes later. The action described above took place between 9:00 and 10:30 PM. Apr. 27. 8 mi. S Whitewater, 6100 ft., Navajo Co., Arizona Several Elf Owls active about our camp in yellow pine evergreen oak country after complete darkness had set in. At least 3 present, concentrating activity around a snag with many cavities in it. Whistled note (see you very high at first), trashing off. Also --- chattery attempts to collect these were to no avail.