JESimpson,1938 27. 775± ft., Tinajas delos Papagos, Sierra del Pinacate, Sonora March 21,1938, continued Set out 50 mousetraps and fifty livetraps. March 22,1938 Caught 2 Perognathoss intermedius in black lava field (5744,5745,JES) and 2 Dipodomys merriami (5746,5747,JES) in the mousetraps; 1 Dipodomys merriami in the livetraps(578) The kangaroo rats were taken in the light sand of the washes which run thru the dark lava. The testes of each of these males were descended. Also 4 (one?) Peromyscus eremicus, in lava. In the afternoon shot four lizards (Uta?) in the dark lava fields. Late afternoon set out 50 mousetraps and 50 livetraps. About 4:20PM shot a bat (5755, Pipistrellus hesperus) in the large wash that leads to the Papago tanks; an hour later shot 3 more bats (538, Myotis californicus; 540?,560? P.hesperus in the same wash near the tanks where they were seen to come to drink. Large numbers (50+) of mourning doves also come to the tanks for water in the dusk; three shot for the table. March 23,1938 Caught one Perognathous intermedius (574) atop a rocky hill in the middle of large, level, small-rock, dark lava field; the other 49 traps set in this field yielded nothing, but 20 Peromyscus eremicus. The 50 live traps set in coarse-dark-sand-and-rock level lava field yielded nothing. Set 50 live traps and 50 mouse traps in the coarse sand (and creosote) at the base of Sykes crater, two miles.