Oct 1931 Brew Creek, 7000 ft., Kauch Range 60 # Sept. 22, 1931 Perognathus audeensis. The light colored Microdip. were in the same type of association as the dark. No difference could be noted. They were scattered about the trap line between the dark kind. The soil here is quite sandy. Going up the road 5 miles nearer Brew Creek our second trap line placed yesterday A.M. I found that out of 47 traps placed I had 3 Microdipodops and 1 Perognathes aude. This country was much rockier than where we caught the light colored Microdipodops. Only the dark type were in any of our traps. Going a mile and one-half closer to Brew Creek where I placed out 36 traps last night I found 4 Microdipodops (dark) and 1 Dipodomys leucipes. Arrived back at Brew Creek, where Hall stayed for the night, at 9 A.M. A trap line that I placed up along the sides of the hills and down in the meadow contained 1 Peromyscus m. sonoriensis, 2 Perognathus parvus, 1 Eutamias on-fictus, and one