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16 THE CONDOR Vol. XVII two males, this being most apparent in the heavier markings on the tarsus and toes of the former. There is some indication that the arid climatic conditions surrounding this form are conducive to rather more marked fading of plumage in the course of months, than is the case with the California bird; and this too despite the fact that the mode of life of the two subspecies is practically the same. In the juvenile example of huachucae the newly grown rectrices and remiges are noticeably darker than is the case with the adults, taken in April and July. In typical occ,dentalis, taking specimens similarly comparable, the difference is inappreciable. Careful comparison of the two series, from California and from Arizona, respectively, shows the following dissimilarities, aside from the generally paler coloration of the latter subspecies. Facial discs: In huachucae these are noticeably grayish. The ground color of the anterior two-thirds is practically pure white, of the posterior margin, light brown. There is little variation in the three specimens. In occidentalis this part is quite uniformly dark brown, with a limited grayish area anter- iorly. White spots on individual body feathers: Careful analysis of patterns of separate feathers from any part of the body shows throughout an extension of the white areas, with corresponding reduction in brown, in huachucae as com- pared with typical occidentalis. This is quite noticeable, for example, in the plumage of the upper breast, where a feather that, in occidentalis, is brown with two white spots, in huachucae frequently.will have the two spots coa- lesced, producing a barred feather instead of a spotted one. Tail bars: In huachucae the tail bars are broader, and are more nearly pure white. The tendency in occidentalis is for them to become broken into spots. In both races the number of tail bars varies in different individuals and on different feathers, ranging from six to eight in number. White spots on outer webs of primaries: In huachucae these are broader, more nearly white, and generally more conspicuous. Throat and median line of abdomen: The throat patch in huachucae is pure white, and covers a relatively large area. In occ.,dentalis the unmarked portion is rather more restricted, and is frequently bully or grayish in color. The center of the abdomen is more nearly pure white in huachucae, as com- pared with the duskier hue usually seen in occidentalis. Tarsus and toes: In the two adult males of huachucae tarsus and toes are almost pure white, sparsely flecked with pale brown. The single adult female at hand has these parts much more heavily marked, being in this respect quite like certain examples of occidentalis, though in most specimens of the latter form the legs are somewhat darker. It is noteworthy that in the juvenile male of huachucae tarsus and toes are pure white, unmarked, while the juvenile female of ocvidentalis at hand has these parts heavily marked. The inference that might be drawn from these facts is that the observed variation in color and markings of toes and tarsus is to some extent due to difference in sex. This, however, is not corroborated by conditions in the series of adult occident- alis. In the two juvenals described in my previous paper on the species (Univ. Calif. Publ. Zool., vol. 7, 1910, p. 7), toes and tarsus were pale colored and un- marked, but unfortunately the sex of these birds had not been ascertained. Under tail coverts: These are parti-colored feathers of white and brown. In huach?tcae the white areas are the most extensive, while in occidentalis the