Mayhew 1963 Journal 10. April 6 Gran Desierto Trip, Sonora, Mexico at 0900. We looked for Phrynosoma micelli for the first 10 miles. Only 1 live one was seen. Lots of immature Diposauma dorsalis were seen all along the road, as well as a few Callisaurus draconoides & Uma notata. By noon it was getting too warm for P. micelli, so we drove east of San Luis about 90 miles to see what the country was like, & to see if there was additional suitable habitat for P. micelli. No better habitat was found, so we returned to San Luis. We crossed the U.S.-Mexican border at 1800. Then we drove to the Ogilby Road & camped for the night. We drove 245 miles today. April 7 Glamis area, Imperial Co., Calif. We awoke at 0800 because the sky was completely overcast. I drove down Highway 80 to get some pictures of the dunes in that area, then returned to our campsite to pick up the others. Then we drove to Glamis by way of the Ogilby Road. We began to look for Phrynosoma micelli between the canals at 1045, and continued looking until 1730 (sunset - 1800). We found 11 live & 6 DOR P. micelli during that period.