Palmer 1937 March 7 contd. Itinerary 1 mi. S Antioch, 100 ft., Contra Costa Co., Calif. Cont'd. Along the side of the road. Most of these were set in well marked runways, which appeared to be those of Microtus, in the tall grass. Ate in Antioch and went back to 2 1/2 mi. S Antioch. to sleep. This A.M. found 18 Peromyscus maniculatus in 24 traps on the hill - 2 1/2 mi. S Antioch, 250 ft., Contra Costa Co., Calif. Many traps had been sprung by sheep. Went on down to 1 mi. S Antioch, 100 ft., Contra Costa Co., Calif.. The 40 traps there had caught: Reithrodontomys megalotis, 3 ♀; Peromyscus manicu-latus, 1 ♀; Mus musculus, 6- (4♂,2♀). Returned to Berkeley via Somerville, Northville, Walnut Creek, Lafayette & Claremont Canyon.