Localities: Oaxaca (SCL. P. Z. S. 1859, 390); Cuba (CAB. Journ. III, 465; GUNDL. Rept. 1865, 225, west end); Arizona (COUES, P. A. N. S. 1866, 50); Brazil (PELZ. Orn. Bras. I, 10); Buenos Ayres (SCL. & SALV. P. Z. S. 1868, 143); Chile (PHILIPPI, Mus. S. I.). In view of the untangible nature of the differences between the American and European Short-eared Owls (seldom at all appreciable, and when appreciable not constant), we cannot admit a difference even of race between them. In fact, this species seems to be the only one of the Owls common to the two continents in which an American specimen cannot be distinguished from the European. The average plumage of the American representative is a shade or two darker than that of European examples; but the lightest specimens I have seen are several from the Yukon region in Alaska, and one from California (No. 6,888, Suisun Valley). Not only am I unable to appreciate any tangible differences between European and North American examples, but I fail to detect characters of the least importance whereby these may be distinguished from South American and Sandwich Island specimens (“_galopagoensis_, Gould,” and “_sandwichensis_, Blox.”). Only two specimens, among a great many from South America (Paraguay, Buenos Ayres, Brazil, etc.), are at all distinguishable from Northern American. These two (Nos. 13,887 and 13,883, Chile) are somewhat darker than others, but not so dark as No. 16,029, ♀, from Fort Crook, California. A specimen from the Sandwich Islands (No. 13,890) is nearly identical with these Chilean birds, the only observable difference consisting in a more blackish forehead, and in having just noticeable dark shaft-lines on the lower tail-coverts. [Illustration: _Otus brachyotus._] In the geographical variations of this species it is seen that the average plumage of North American specimens is just appreciably darker than that of European, while tropical specimens have a tendency to be still darker. I know of no bird so widely distributed which varies so little in the different parts of its habitat, unless it be the _Cotyle riparia_, which, however, is not found so far to the south. The difference, in this case, between the American and European birds, does not correspond at all to that between the two easily distinguished races of _Otus vulgaris_, _Nyctale tengmalmi_, _Surnia ulula_, and _Syrnium cinereum_. A specimen from Porto Rico (No. 39,643) is somewhat remarkable on account of the prevalence of the dusky of the upper parts, the unusually few and narrow stripes of the same on the lower parts, the roundish ochraceous spots on the wings, and in having the primaries barred to the base. Should all other specimens from the same region agree in these characters, they might form a diagnosable race. The plumage has an abnormal appearance, however, and I much doubt whether others like it will ever be taken.