Palmer 1935 Microtus californicus Sugarloaf Peak, 1300 ft., 1 mi. E. Stadium, Berkeley, Alameda Co., Calif. Feb. 27 Caught 4 in 51 traps. These were: 3 adult ?? and one immature (54?) All were taken in extensive runways in the short grass on the W side of the peak. Most of the runways were old and for the most part, passed through dry grass. There were numerous burrows in these systems but not all showed signs of occupation. Cut grass was found in only a few places in the runways and only one spot was found where there were any feces. This spot had evidently been in use for some time as the feces were rather thickly piled over the small bare area at the end of a short runway. Two of the ?? contained embryos. One had six 28 mm. embyos, The other had four 10 mm. embyos. One ? discarded also appeared to be pregnant.