The Olive-Backed Thrush of California
The Olive-backed Thrush of California.-All through July, 1923, Olive-backed Thrushes were present in fair numbers, and in full song, in the dense alder clumps and thickets that fringe the mountain meadows in the vicinity of Mammoth, Mono County, California (altitude 8000 feet). Four specimens were taken; one by the writer, now no. 12805. collection of Donald R. Dickes. and three bv Dr. Love Miller. Beside these, there is a specimen, no. D 429, collectionof ’ D. R. D., taken at-Mammoth, July 8, 1916; by Laurence M. Huey. This station lies on the eastern slope of the Sierras. No nests were found, but the condition of the specimens which were taken left no doubt as to their breeding activity. There is also in the Dickey collection a male, no. 11920, COB. of D. R. D., taken July 17, ’ 1916, on the North Fork of the Yuba River, at Sierra City, Sierra County (altitude 4500 feet). This locality is on the western slope of the mountains. All of these birds, as well as a female, no. 7856, ~011. of D. R. D., taken June 18, 1908, at Stehekin, Chelan County, Washington, are notably grayer and less rufescent dorsally than birds from the eastern United States. In fact, the latter are more or less intermediate between ustulata and almae, just as Oberholser stated in his description of Hylocichla ustulata almae (Auk, xv, p. 304). Eastern birds are also more . heavily spotted below. Therefore I have no hesitancy in using the name almae for the western specimens enumerated above. The only uncertainty is in connection with which specific name to employ. Based on California birds alone, these should be called Hglocichla swainsoni almae, but as intergradation may occur in other regions, I do not at present feel justified in advocating such procedure.-A. J. VAN ROSSEM, Pasadena, California, November 24,1924.
