Hopper Peromyscus maniculatus 3 mi. W Dunness, Marin Co., June 25, 1938: 2 in 70 traps, only a few of which were set on dry ground; the rest set in marshy area along the Rd. Reyes Road. 2 mi. SE Olena, Marin Co., June 26, 1938: 60 traps set on exposed SW-facing slope in grazed grass and at borders of rocks with live oak and poison oak thickets near netted 2 animals—these caught at bases of rocks. Other traps out in grassy spring—probably by Peromyscus No trap over 100 yds from oak-brush-studded canyon. 1½ mi. SW Five Brooks, Marin Co., June 27/8: 1 in 4 traps set in heavy Baccharis, poison oak, et al. 2 in 30 traps set in marsh surrounded by Baccharis; these, as usual, taken on dry ground at edge of marsh. Mangumto, salt marsh, Marin Co., June 28: None taken in marsh.