41901, ♀. ¼
54338, ♀. ½
12006, ♀. ¼
19124, ♀ ? ¼
- 9128. Haliaëtus leucocephalus.
- 41901 : 12006 : 19124. Aquila chrysaëtus, var. canadensis.
- 54338. Archibuteo lagopus (tarsus from behind).
Gen. Char. Form robust and structure powerful; the bearing and general aspect that of Buteo and Archibuteo. Wing long, the primaries long and strong, with their emarginations very deep. Tail rather short, slightly rounded or wedge-shaped. Bill stronger than in the preceding genera, its outlines nearly parallel, and the tip somewhat inclined backward at the point; commissure with a more or less prominent festoon; nostril narrowly oval, vertical; skin of the cere very hard and firm. Superciliary shield very prominent. Feet very strong, the membrane between the outer and middle toes very well developed; tarsus less than twice as long as the middle toe; outer toe equal to, or longer than, the inner; claws very long and strong, very much graduated in size; scutellæ of the toes small except on the terminal joint, where they form broad transverse plates; tarsi densely feathered all round down to the base of the toes; tibial plumes well developed, loose-webbed, their ends reaching down to or beyond the base of the toes. Feathers of the nape and occiput lanceolate, acute, and distinct, forming a nuchal “cape” of differently formed feathers. Third to fifth quill longest; first shorter than the seventh; outer five or six with their inner webs deeply emarginated.