cenchroïdes_ Australia and Tasmania. It is remarkable that no Kestrel inhabits Jamaica or Bourbon, though Cuba and Mauritius are respectively so near them. _Erythropus vespertinus_, the Red-footed Falcon, which wanders to Britain, but breeds from Eastern Europe and Algeria to Krasnoiarsk, where it meets the Eastern Asiatic _E. amurensis_, is lead-grey in the male, with browner tail, chestnut thighs and vent region; the female being barred with blackish above, and having the head, nape, and under surface rufous. The cere, orbits, and feet are red. Both forms migrate to South Africa, keeping more to the west and east respectively; the latter, which crosses India and Burma, being distinguished in the male by white under wing-coverts, and in the female by the absence of rufous on the head, neck, and brown-spotted breast. In general habits like Kestrels, these birds are more gregarious, and breed in company. _Hypotriorchis subbuteo_, the Hobby, nests sporadically in England, and extends thence to North Africa and Japan, occurring in the Canaries and migrating to South Africa, North India, and China. Both sexes are slate-coloured, having buff lower parts with black streaks, reddish vent, white throat and sides of the neck, and a black stripe down the latter. This bold and dashing little Falcon, easily recognisable by the extremely long wings, which give it a Swift-like appearance, is usually seen poised aloft, or rapidly pursuing the insects and birds which form its food. The note is shrill; the three to five eggs resemble closely freckled pinkish specimens of those of the Kestrel, and are {177}deposited late in the season in disused birds' nests. The statement that it broods on the eggs of the Kestrel needs further proof. _H. eleonorae_, the largest Old World species of the genus, occupying the Mediterranean basin from Spain and the Atlas to the Levant, while straying to Mauritius, is uniform sooty-black; but some individuals never become sooty, and immature examples precisely resemble the Hobby. The habits are like those of its congener, but the two or three eggs are larger, and are laid in holes in cliffs, or upon the bare soil on stony flats of desolate islands. The very similar _H. concolor_ ranges from the Red Sea to Madagascar; _H. cuvieri_ inhabits the Ethiopian Region; _H. ophryophanes_ is described from Colonia; _H. severus_ extends from India and Ceylon to New Britain, but not to Australia; _H. lunulatus_ from Flores to the Duke of York Island, with Australia and Tasmania; _H. fusco-caerulescens_ and _H. rufigularis_ from Mexico to Argentina, the former moreover reaching the southern United States and Patagonia. The powerful _H. diroleucus_–perhaps referable to the genus _Falco_–occurs from South Mexico to Peru and Brazil.