W. Muenster 1943 Perognathus californicus May 30, Galician Range, 1500 ft., 5 1/2 mi. ENE Soledad, Monterey Co., Calif. Dry grass. June 3, Santiago Springs 2700 ft., 8 mi. E + 1 1/2 mi. S Guimlar, SL Co., Calif. 30 immature were caught in live snap traps. And one immature was caught in a live trap. The traps were set on a hill side where junipers and Stanleya were the dominant plants, other Buckwheat, Baccharis and two Compositae were also present. Small holes were present near three of the sets. The soil is loose, but only occasionally are there bare spots not covered by grass. June 4, One immature was caught high on the hill set up yesterday. The trap was placed under a juniper in an open run. An adult male was caught in a live trap near the bottom of the hill slope, almost at the canyon bottom between the hill I was setting on and the next hill. The mouse was dead. The trap was set in the shade of a lush Compositae. During the afternoon we dug out a Pocket Mouse burrow near our camp. It is situated in the bank of a dry stream bed. It is surrounded by grass on the surface near the hole and all about the vicinity except for a small area where work ground was apparently thrown out of the tunnel system.