primaries are very narrowly bordered with white at the ends. Tail with seven or eight very narrow bands of white, those on the middle feathers purely so, becoming obsolete exteriorly; the last is terminal. Eyebrows, lores, and face grayish-white, the grayish appearance caused by the blackish shafts of the feathers; that of the face continues (contracting considerably) across the lower part of the throat, separating a large space of dark brown, which covers nearly the whole throat, from an indistinct collar of the same extending across the jugulum,—this collar uniting the lower ends of the auricular and cervical dusky bands, the space between which is nearly clear white. Ground-color of the lower parts white, but everywhere with numerous very regular transverse bars of deep brown, of a tint more reddish than the back, the brown bars rather more than half as wide as the white ones; across the upper part of the breast (beneath the dark gular collar) the white invades very much and reduces the brown, forming a broad lighter belt across the jugulum; below this the brown bars increase in width, their aggregation tending somewhat to a suffusion, giving the white jugular belt better definition. On the legs and toes the bars are narrower, more distant, and less regular. The whole lining of the wing is barred just like the sides. The dark brown prevails on the under surface of the primaries, etc.; the former having transverse, irregular, elliptical spots of white, these touching neither the shaft nor the edge: on the longest quill are seven of these spots; on all they are anterior to the emargination. ♂ (49,808, Nulato, Alaska, April 21, 1867; W. H. Dall). Wing-formula, 3, 4–2–5–6–1. Wing, 9.00; tail, 7.00; culmen, .70; tarsus (of another specimen; wanting in the present), .90; middle toe, .82. ♀ (49,807, Nulato, April 20; W. H. Dall). Wing-formula, 3, 4–2–5–6–7=1. Wing, 9.00; tail, 6.80; culmen, .70; middle toe, .80. HAB. Arctic America, south in winter into northern United States; Wisconsin (DR. HOY); Massachusetts (DR. BREWER; MAYNARD); Dakota and Montana (Mus. S. I.). The Hawk Owl of North America is to be distinguished from that of Europe and Siberia by the same characters which distinguish the American Sparrow Owl from the European, namely, much darker shade of the brown and its greater prevalence. Three perfect specimens of the Old World bird (a pair from Lapland, and a specimen from Kamtschatka, Petropawloosk, W. H. Dall) agree in prevalence of the white over the head above, the confluence of the spots on the scapulars forming a larger, more conspicuous patch, and very broad and almost immaculate jugular belt; the brown bars beneath are very much narrower than in the American bird, and the tint is not different from that of the back. The legs and toes are scarcely variegated. While acknowledging the identity of the two representative forms, the differences are such as to entitle them to separation as races.