Thaler 1958 Species Account July 15 Perognathus fallax Mesan Valley, 5.3 mi. W Vallecitos Stage Station San Diego Co. Calif. I took two there in snap traps on the valley floor last night. Here the primary vegetation is some bush and grass. The vegetation of this valley is strikingly different from that in the valley in which the stage station is located. July 16. another of these was taken this A.M. in the same trap line as those mentioned above. It was frozen and prepared later. (579)