Hooper, 1937 Berkeley, Alameda Co., Calif. Feb. 15, on the night of Feb. 13. The catch this morning was: 2 Mus musculus - 1 in "Benson" livetraps; 1 in snare trap; 3 Microtus californicus - in gosh traps; 4 Reithrodontomys megalotis - 1 in can trap, 3 in gosh traps. The two house mice were discarded, the live harvest mouse confined to a cage, and the remainder made into study skins. All of the mammals preserved were trapped in California. No embryos were found, though the testicles were enlarged in one Reithrodontomys. 1 mi. W Avon (salt marshes), Contra costa Co., Calif Feb. 28, Left Berkeley at 2:30 yesterday P.M. in company with Mr. D.A. Johnson, and drove in M.V.Z. Dodge truck to Avon. Avon is a refinery town located about 4 mi. E of Martinez and on Suisun Bay; the place lies on a "spit" of land which is above normal high, right tide level. Surround ing it are extensive marshes covered with Salicornia chiefly, but with