Hoopu Perognathus inornatus vicinity of Oakley, Contra Costa Co., Caly. June 21, 1938 Along the Marsh Creek Road just before it leaves the foothills to unit onto San Joaquin Valley floor and around Oakley, there substrate is predomi- nantly sandy - some even driftable, especially after having been plowed or disturbed in some such way. 79 mouse traps set on this sandy ground in an uncleared area grew to Adenostema chiefly, with a few oaks + clumps of Artemesia, rattled nothing. So far the only record of these small pocket mice is from Owl Pellets. See article in Condor by D. Stone.