Erickson 1934. testoma albigula West base of Castle Dome, 1400 ft. Yuma Co., Ariz. Jan. 11. No. 175 taken under goatnut bush along edge of small gully on mesa; no house located in radius of 50 ft., one observed 100 ft. or more distant along same gully. Bates Mill, Pima Co., Ariz. Jan. 30. No. 262 taken in trap set on run from small house at side of small gully on mesa, house built mostly of cholla joints around a branching deer horn cholla; palo verde and creosote bushes near and extend over cactus to some extent. Bates Mill, Jan. 31. No. 272 taken between 8 a. m. and 5 p. m. in trap set in runway from rat house on lava hill N.E. of Mill; from position in trap was probably returning to house. House large pile of sticks and cholla joints in spaces of lava slide. 1 mi. east of Colago Mill, 1100 ft. Pima Co. Ariz. Feb. 5, No. 307 taken on crest of small granite hill near house of sticks and cholla joints built in rocks, no other individual secured at 6 other rat houses along sides of hill. Barker, 350 ft., Yuma Co., Ariz. Feb. 24. No. 415 taken in dry tule filled ditch 5 mi. south of Barker, cultivated field on one side, open mesquite stand another.