field - 1934 Colorado R., 3 mi. N., 2½ mi. W. Camp Mohave, Mohave Co., Ariz. January 24, 1934 Caught in traps 3 Dipodomys merriami 8 Peromyscus eremicus Spent the morning putting up the 3 D. merriami and 7 of the P. eremicus The wind was blowing very hard all afternoon, so the hunting was bad. Saw an Albert towhee, a cottontail rabbit, and late in the afternoon I happened on a grey fox in the grass. It ran straight away from me, too rapidly to allow my getting a shot at it. Tonight set out 50 traps along bank of river among relatively large wil- lows. January 25, 1934 Caught in traps - nothing. This, at first sight, seems rather peculiar, since back away from the river only a short distance (in arrow-weed) the mem- bbers of the party caught P. eremicus and D. merriami. The 50 traps were set out in the hopes of catching Peromyscus boylii, as some were caught across the river in practically the same kind of association.