History of British animals - University of Guam Marine Laboratory

48 BIRDS. ACCIPITRES. Falco.ACCIPITRES.RAPACIOUS BIRDS.I. DIURN7E. Hawks.— Bill covered at the base with a cere,in which the nostrils are lodged. Eyeslateral. Outertoe (with the exception of Balbusardus) incapableof havingits positionor motion reversed.* Macropter^e. Noble Hawks.— Second quill-feather longest;the first nearly equal.Bill arched fromthe base.•fClaws flat or grooved on the under side.Falco.Gyrfalco.•f-f Claws rounded on the under side.Balbusardus.fft•• Brachypter.e. Ignoble Hawks. — The third or fourth quillfeatherlongest; the first very short.Tail forked.Milvus.Tail not forked.1.Space between the bill and eye feathered.Pernis.2. Space between the bill and the eye naked or hairy.a. Bill straight at the base, and bent at the extremity.Aquila.aa. Bill bent from the base. Tarsi plated.b. Ear-feathers forming a collar like the owls.Circus.bb.Ear-feathers plain.Buteo.II. NOCTURM/E. Owls.—Bill without cere.Eyes large,directed anteally; surrounded with a circle of radiatingwiry feathers, which serve to cover the base of the billand auricles. The external toe capable of having its positionand motion reversed. On the top of the head, insome species, are two tuftsor ears.of long feathers, termed horns* Concha of the ear occupying the whole side of the head. The firstor second quillthe longest. Wings about the length of the tail,•f-Bill arched from the base. Head with horns.Otus.•ff Bill straight at the base. Head destitute of horns.Aluco.