Oct., 1935 2 mi. E. Bishop, Inyo Co., Calif. May 21, 1935 Skull only 790 Reithrodontomys m. megalotis 143-71-18 tentaged tests 791 " " " 133-70-18 .. 792 " " .. 130-66-16 .. .. 793 Microtus c. vollicola 170-40-23 1 mi. W. Laws, Inyo Co., Calif. May 23, Laws is a small town 5 miles NE. Bishops; it lies at the end of the railroad line (Mohave -> Laws) and is about 3/4 mi east of the Owens River, actually lying in the old river bed. My collecting locality is, thus, on the west bank of the river bed and 1/4 mi. west of the present river channel. The bottom lands are covered with grass and serve as forage ground for cattle. Mammal signs, other than that of Lagamorpha, is scarce. However, on the adjoining, sandy bank near sage bushes, burrows, tracks, and fecal material is fairly abundant. It was in this latter habitat that I set out fifteen traps. Black-tailed jackrabbits (Lepus c. deserticola) and Cottontails