Measurements.—Thirty-one males and 19 females from Washington average, respectively: total length 169, 164; length of tail 90, 86; hind foot 22.6, 21.8; ear 5, 5.
Distribution.—Southeastern Washington south of the Snake River, the area on the north side of the Columbia River in Klickitat County, and the Yakima Valley area as far north as the Vantage, Kittitas County (W. W. D.). Other marginal records are: Kennewick (W. W. D.), Atilla (W. W. D.) and Walla Walla (E. S. B.).
Remarks.—Dichromatism seems to be rather common in Perognathus p. parvus—so common that [Osgood] (1900: 35) recognized both a "red" and a "gray" phase. [Anderson] (1932: 102) found no dichromatism in P. p. lordi in British Columbia. A single specimen from the Grand Coulee at Dry Falls, Grant County, does show dichromatism. It is even more red than the reddest topotypes of parvus examined.
Seemingly the recessive gene for red is still present in lordi, or has mutated anew. When present, the color is deeper and brighter than in the parent population, in keeping with the heavier pigmentation of the race lordi.
Perognathus parvus lordi ([Gray])
Abromys lordi [Gray], Proc. Zoöl. Soc. London, p. 202, 1868.
Perognathus lordi [Merriam], N. Amer. Fauna, 1:28, October 25, 1889.
Perognathus lordi lordi [Miller], U. S. Nat. Mus. Bull., 128:279, April 29, 1924.
Perognathus parvus lordi [Davis], Recent Mamm. of Idaho, p. 266, Caxton Printers, Caldwell, Idaho, April 5, 1939.