Gymnogyps californianus February 13, 1946 Hopper Canyon, QI.X. mouth (facing in) after 3+ minutes, while other en- tered hole but turned as head protruded - they were still there at 9:40. Retrogressing - 21 cawors were seen at once in the air about 9:15. I contin- ed down the trail passing about 200 yds. from and 100+' below the adult pair - the ritter stood & both seemed to watch me, one with head down most of the time. The pair left about 10:07 when I was well past them. At 10:00 I saw 3 cawors in air over North Slope, this same pair, & 4 (2 ad., 2 imm.) still at Whitewash Ledge. One youngster soared (flap glided) down Cawor Canyon when I was 300+ yds. away, than an adult 1+ min. later, then other adult, & 5+ min. later the last youngster. The adult pair & last 2 on Ledge left while I was rested about 200 yds. from Big Cave. Last youngster gave 8 successive flaps in flap gliding. Liked to end of tractor trail - 100+' from Cawor creek - then crossed creek & climbed trail through the brush to foot of Cawor Cliff, then went W. at cliff foot to Wales nest (arrived 10:45). Collected 30+ bones, tooth fragments, & seashells (!) from inside the cave & for 20+' below cave mouth. The shells & all but 1 or 2 small mammal bones were outside. There were several film & flash globe wrappers, a film spool, broken flash globes, & 2 cigarette butte