Gymnogyps californicus April 13, 1946 Hopper Canyon Cliff 7/0 immatures by then, the clouds having formed since 10 a. m. at about 6000 ft. level. At 1:05 one adult alighted on a ledge below Whitewash Ledge + 3 ± min. later soared toward Roost Tree (not visible). At + 1:08 another adult spiraled over us, feet down, & alighted on Whitewash Ledge. An imm. cir- cled over Big Cave for 5 ± minutes then departed. The perched adult had cheeks puffed out (not red) and ruff up high. Ed photo'd this bird in 35 mm. About 1:40 this adult left & (some?) lit in a shaded pothole 40 ±' below the former perch. The bird moved head every 5 sec. or less as if looking about. At 68° F, 1:47 the adult took off as if toward Roost Tree. 2:55, one imm. alighted atop cliff over Whitewash Ledge. It scratched head by squatting down & scraping sides of head on rock several times. Two other immatures alighted 10 ±' from the first - these wrestled heads a bit. One imm. flew to cliff top above Big Cave, then back to group 2 ± minutes later. At 3:05 07 there were 2 adults & 4 imm. within about 15' on the cliff top. Two imm. picked at each others ruff & head as if playfully; adults preened; other imm's. picked at rock by their feet. One imm. off about 3:09 & landed atop cliff 50 ±' N. of pool about 3:13, 3:18 a third adult alighted by other 2 - 3 adults & 3 imm. within about 15'