Aug 27, 350 The Peña Blanca area is shown on USGS Ruby Quadrangle surveyed 1939, edition of 1942. The Alamo canyon locality mentioned in previous notes as the unnamed canyon ex- tending west from Peña Blanca spring, Alamo Canyon in the SE corner of the quadrangle. Alamo canyon drains northward into the Ysla River drainage while Sycamore canyon waters eventually reach the Rio Magdalena in Sonora. True Rana tarahumarae occurs on both sides of the divide. The Rila which we collected in Alamo Canyon looks different from Rila ditamae of the Sycamore Canyon, and may represent a different species, being in another drainage. From the description in Dr. Mellers' paper on Rila (Copeia 1949, No. 2.) it appears that the pool in Sycamore canyon where we collected the R. tarahumarae is the same one in which he observed the Rila.