Ash-coloured or Black-capped Hawk, Falco atricapillus, Wils. Amer. Ornith. v. vi. p. 80. Falco palumbarius, Bonap. Syn. p. 28. American Goshawk, Falco atricapillus, Nutt. Man. v. i. p. 85. Accipiter (Astur) Palumbarius, Swains. & Rich. F. Bor. Amer. v. ii. p. 39. Goshawk, Falco palumbarius, Aud. Orn. Biog. v. ii. p. 241. 24. 2. Astur Cooperi, Bonap. Cooper's Hawk. Plate CXLI. Fig. 3. Adult Male. Plate XXXVI. Young Male and Female. Tail rounded, tarsi moderately stout. Adult male dull bluish-grey above; the tail with four broad bands of blackish-brown, and tipped with white; the upper part of the head greyish-black; lower parts transversely barred with light red and white, the throat white, longitudinally streaked. Female similar, with the bands on the breast broader. Young umber-brown above, more or less spotted with white, the tail with four blackish-brown bars; lower parts white, each feather with a longitudinal narrow, oblong, brown spot. _Male_, 20, 36. _Female_, 22, 38. From Louisiana northward, and all over the interior, in winter. Some breed in the United States. Columbia River. Cooper's Hawk, Falco Cooperii. Bonap. Amer. Orn. Young. Falco Cooperii, Bon. Syn. App. p. 433. Young. Stanley Hawk, Falco Stanleii, Aud. Orn. Biog. v. ii. p. 245. Adult Male. Stanley Hawk, Falco Stanleii, Aud. Orn. Biog. v. i. p. 186. Young. 25. 3. Astur fuscus, Gmel. Sharp-shinned Hawk. Plate CCCLXXIV. Adult Male and Female. Tail even, tarsi extremely slender. Adult male bluish-grey above; the tail with four broad bands of blackish-brown, and tipped with white; upper part of head darker; lower parts transversely barred with light red and white, the throat white, longitudinally streaked. Female similar, more tinged with yellow beneath, and with the bands on the breast broader. Young umber-brown above, more or less spotted with white, the tail with four dark brown bars; lower parts white, each feather with a longitudinal narrow, oblong, brown spot. Miniature of _Falco Cooperii_, and intimately allied to _Astur Nisus_. _Male_, 11-1/4, 20-1/2. _Female_, 14, 26. Generally distributed. Not very abundant. Migratory. Slate-coloured Hawk, Falco Pennsylvanicus, Wils. Amer. Ornith. v. vi. p. 13. Adult Male. Sharp-shinned Hawk, Falco velox, Wils. Amer. Ornith. v. vi. p. 116. Young Female. Falco velox, Bonap. Syn. p. 29. Falco fuscus, Bonap. Syn. Append. p. 433. Accipiter Pennsylvanicus, Slate-coloured Hawk, Swains. & Rich. F. Bor. Amer. v. ii. p. 44. American Brown or Slate-coloured Hawk, Nutt. Man. v. ii. p. 87. Sharp-shinned or Slate-coloured Hawk, Falco fuscus, Aud. Amer. Orn. v. iv. p. 522. Adult. GENUS XI. CIRCUS, Bechst. HARRIER.