Mayhew 1958 Sept. 19 Journal 103. Colorado Desert, Calif. the surface temp. was 36.5°C. One adult of Uma notata was captured lying partly exposed on the surface. Some other adult Uma & many young were seen, but this was the only animal caught. Two juvenile Crotalus erastes were seen during this stop. As we began to drive toward Brawley in the dark (about 1825) an adult Urosaurus graciosus was collected from the road (still in the dunes). A short distance further on a ♀ Uma notata was collected DOR & preserved for her ovaries. A little later a juvenile Crotaphytus wislizeni (1900) was collected on the road, followed a few minutes later by an adult Coleonyx variegatus. At this time (1915) the air temp. was 32.2°C., the soil surface temp. was 31°C., & the road surface temp. was 35.5°C. We drove past the dunes, & on the outskirts of Brawley we collected an adult Bufo woodhousei in the road. After leaving Brawley, we drove to Ocotillo Wells. We turned south at this point toward the gypsum mine to set up camp. Along this road we collected one more adult Coleonyx variegatus and 2 juvenile Phyllodactylus dacentatus. In addition, we killed one Crotalus erastes at the