E.L. Kadetun 1954 Buffo boreos (22) may 7 Stoneman meadow, 4000 ft., Yosemite Valley, Mariposa Co. Colig. (from RCS field notes) weeks ago. Also water tray in pool where smallest Buffo toads found 2 weeks ago. may 8 Water 17.7° C.; air ½" above ground in damp place next to pool 8.7° C. 9:40 p.m. Oil on water. Tadpoles dead. Downy owl calling from tree at E edge of meadow. may 9 Few toads (Hygin and Buffo still alive in above pond. One Buffo about ½" total length seen. Black oak fully leafed out. According to RCS Stoneman meadow only tad now seen tadpoled. He asked Hubbard to try to save Court. Center had from same fate. Uncertain as to how extensive practice is or how long it has been carried out in Valley. Seek specific information next trip to Valley. U.C. parasitologist indicated to determine that topic was added to oil in mosquito control. may 13 Conversation with William L. Bill at Administration Bldg., Yosemite Valley, concerning mosquito control. Such a program has been carried out 4-5 years after mosquito problem became "almost unbearable". Areas affected are Tuolumne Meadows and Valley, less oily here lower sections of Valley but almost all standing water treated. Bill mentioned