R. Zweifel Rana boylii Mar. 23, 1951 267 2.4 mi SE Clayton, Contra Costa Co., Calif., 600' Along about 300 yards of stream I saw only four frogs, of which two were caught. The water temperature was 17.8°C. The stream (Marsh Creek) had been disturbed recently by road construction, which may account for the scarcity of frogs; or perhaps it is merely a little early in the season. The hillsides to the south have a thick growth of digger pine and oak, to the north scattered oaks over grass. The stream itself is subject to the full sunlight, the few saplings are not yet in leaf. The dorsal color of the frog is light brown, with a slightly yellowish tinge. There is only the slightest suggestion of a concentration of melanophores to form spots. The light head bar is only faintly indicated across the front of the eyelids. The throat is immaculate except for the edges of the jaw.* The iridic granulation is highly developed. One of the frogs laid four eggs in the jar within a couple of hours after capture. *The head of the boys has scattered melanophores.