Crickson 1934 Dipodomys merriami West base of Castle Dome, Yuma Co., Ariz. Jan. 10, 1934 A male and a female taken within 25 ft. of each other on mesa near giant cactus, creosote and goat nut bushes, a Perognathus baylgi Taken within 5 ft. of one; soil somewhat finer at this point than on most of mesa. West base of Castle Dome. Jan. 11, 1934 Another individual taken under creosote bush, on mesa. Welter, Yuma Co., Arizona Jan. 12, 1934. One individual taken on sandy soil at NE edge of town; tracks numerous on this soil near where specimen taken; Tinajos Altas, Yuma Co., Arizona. Jan. 17, 1934 One individual taken in 35 traps placed on mesa about 100 ft. from base of mountains, in shallow gully; soil coarse sand, almost fine gravel, rocky over much of area.