R. Zweifel April 8, 1935 6.3 mi SSE Clayton, Contra Costa Co., Calif. Two Rana boylii, one R. aurora and four Hyla regilla were collected here. Aurora was common where the riparian growth was thickest, where it actually overhung the bank of the stream. Three large cluster of R. aurora eggs were found attached to cut-tail stems in about eight inches of water at the edge of the stream. The eggs were on the verge of hatching, since when the masses were disturbed, the young tadpoles broke loose & swam out. 7.1 mi. SSE Clayton, Contra Costa Co., Calif. 7 Rana boylii were seen here, one taken (see species account). 3 Rana aurora were seen, two of these in pools under large over- hanging rocks. There is a distinct paucity of riparian vegetation here. Three Hyla regilla were found sitting on rocks on the stream.