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Jan., 1915 THE STATUS OF THE ARIZONA SPOTTED OWL 17 reverse is usually the case. In the California bird the white is in relatively narrow bars, generally not so broad as the brown portions, though in an occa- sional feather the two will be found of practically equal width. Two birds in juvenile plumage are available for comparison, of occidentalis a young female, taken at Forest Home, San Bernardino County, California , August 17, 1913; of huachucae a young male from the Santa Catalina Moun- tains, Arizona, July 7, 1906. The Arizona bird is clothed entirely in the juve- nal down, except for the nearly grown rectrices and remiges; the California bird is somewhat older, and new feathers are appearing on the sides of the body, in the scapulars, and in the wing coverts. There is little difference ap- parent between these jurehals. In fact I am not able to distinguish with cer- tainty any color difference in the down of the two birds, though the Arizona specimen appears to be slightly more tawny where the other is rather more gray. In the newly grown rectrices and remiges, however, there is a differ- ence, these feathers in the Arizona specimen being distinctly of a lighter tint, as compared with the more dusky ones of the California example. As might be expected, examination of so much additional material is pro- ductive of slightly altered conceptions from those derived from the single spe- cimen of huachucae which served as the basis of my first study of the species. The differences between the two forms here contrasted are, of course, of de- gree rather than of kind; and it is to be expected that more extensive suites of skins would reveal considerable variation in characteristics. On the whole, however, taking Spotted Owls from the designated regions, as represented by the quite satisfactory material here assembled, there is no difficulty whatever in 'distinguishing the two forms, Strix occidentalis occidentalis and Strix occi- dentalis huachucae. It may be argued that the comparisons so far made are not final, in that no example of huachucae in fresh fall plumage has been available; and that even though certain appreciable differences are shown in birds taken at ap- proximately the same season in spring or summer, in Arizona and in Califor- nia, respectively, it is not proved that these differences are not due to a greater rate of fading in one region than in the other. This might be partly true of the different shades Of brown shown in the two races (though I doubt it), but the difference shown by the two forms in the relative areas occupied by brown and by white on the parti-colored feathers of which practically the entire plum- age is composed, a maximum of brown in the California bird, a maximum of white in the Arizona race, is a feature that is not dependent upon long wear and consequent fading of the birds' covering. Then again, in the jurehals of the two forms, as described above, the new rectrices and remiges are of dis- tinctly different shades of brown. As shown in the accompanying table of measurements, huachucae appears to be of slightly smaller size than typical occidentalis, though judging from the range of variation shown in the latter series, the apparent size difference in the races may be due to the small number of Arizona specimens examined. How- ever, taking everything into consideration, there seems sufficient reason for the recognition of the Arizona race of the Spotted Owl. The four specimens ex- amined show a certain range of variation, as is to be expected, but any of them can readily be distinguished from the California form. The extensive series of the latter subspecies available does not contain any specimens xvith charac- ters at all like those of the Arizona birds.