Lee Arnold Horse Canyon, 5800ft, Pahrum Pk., Washoe Co., Nevada 1937 Itinerary May 30, the locality of a Coyote which had been in a trap since last winter. We also found out that several years ago squirrels had been abundant near the mouth of the canyon but in late years they have disappeared. I do not know what species these were, however. In the way down valley we set two pairs of gopher traps in holes in an alfalfa field which had been abandoned. I set 50 traps farther down canyon along the dry creek bed and in the scattered brush on the flat and ten sets up a small side canyon. We then went down to the mouth of the canyon and out onto the floor of the desert. Here I set 43 traps. About 1/2 of these were among the bushes on hard, windswept ground while the rest were over hilly, sandy country. In both cases the bushes averaged about 8 feet apart. This morning we broke up camp before going around to the traps. In the three remaining gopher sets that were around camp I had two Thomomys quadritus. On the way to the traps in the mouth of the canyon I picked up a coyote skull which I had been told about. In the traps (50) set along the creek bed I had 4 Perognathus parvus (28+2?) and 2 Peromyscus maniculatus (18+1?). None of the 10 sets up the side canyon had been disturbed. In the sets on the desert floor to the east of Smoke Creek desert I had; 1 Perognathus formosus ♀