El Karleton 1955 Buffa breva May 19 Ahwahnee Meadow 7:30 A.M. Sun just beginning to flood study over azure blue skies. Air temp. 10.1° C. (bull's shd'd) close wet dew-covered grass. Bark B temp. 13.4° C. 1" below surface where water 8-10 " deep. No signs of toads although water temp. is sufficiently high for their activity. Air temp. may be limiting (?) Some locality 5:10 P.M. Switched max-min station to S side Bark B. Also set up tube with Tog and Taylor thermographs inside. Present water temp. 80.5° E. Air 70.5° E. in tube at 6:10 P.M. Byla quiet until about 5:30 after they called intermittently for a short period of minutes. A single adult toad pond A, 10 yards SE of sroy emitted a series of notes from its position 2/3 rd immersed in the water with or so deep. 10-12 notes descending in pitch, not a trill but delivered in rigid order. Called three times. I heard it first about 5:40 from a point 25 yards S of it. The sun descended behind the Valley wall at 6:15. The effect on byla was almost instantaneous as a dozen males began chorusing, moving right out into positions all over pond (or revealing themselves from already occupied positions). No toads heard at this time.