Quast 1948 Dipodomys merriami 1 April 7 E. side Cocopal mts, 21 mi SSE Mexicali, Baja Calif. 1♂ + 1♀ caught at night in open space on coarse sand wash on alluvial fan. April 17 Cerro Prieto, 30 ft 20 mi SSE Mexicali Baja Calif. None caught by my live traps since above. April 25 12½ mi by road south of El Manantial, 2200 ft Baja California One male + one female caught last night in fine gravel wash among boulders (#91, 92). The female had one embryo of 18mm. Temperature dropped to 43° F last night and specimens were in a sluggish state when the traps were opened this morning. April 28 30 mi SE Mesquite 600 ft Baja California Two males caught (#101, 102) in sand under cholla and grease-wood last night. Traps set at 9:30 PM and were baited with bird seed. May 4 Mulege 25+ ft Baja California One male Dipodomys merriami caught by Dr. Benson in Museum special trap baited with walnut and set in sandy wash last night. Growing in the wash was Mesquite, Creosote, and Palo Verde. Specimen was put up by myself (#127). May 7 Bahia Concepcion 13 mi SE Mulege Baja California One female (#149) caught in live traps set among large "Mangle Dulce" bushes in sandy wash N.E. of camp last night. Traps were baited with bird seed. The female contained no embryos.