FALCONS AND ALLIED SPECIES. 173 



mities vary in length and thickness according to the species. 

 The phalanges of the toes are, as usual, two, three, four, and live. 



The Falconinfe prey on quadrupeds, birds, reptiles, fishes, 

 and insects, which they pursue by flying, not by walking. 

 Indeed most of the species, owing to the form of their feet, 

 are incapable of progression on the ground, and when they have 

 to move to short distances, are obliged to leap, with the aid of 

 their wings. They seize their victims with their talons, thrust 

 into them their long acuminate claws, and, when of suffici- 

 ently small size, carry them off to some secure retreat. The 

 bill is not generally used for inflicting wounds, but with it they 

 remove the hair or feathers, previously to eating the flesh, which 

 they tear up with ease, often swallowing the bones. Having 

 filled the oesophagus, which is always capable of being much 

 dilated, they retire to some sequestered place, and remain quiet 

 until the food is digested. The insoluble parts are vomited in 

 roundish pellets, in which the bones are enveloped by the hair 

 and feathers. Their sight is very acute, as is their sense of 

 hearing. Their flight presents modifications, according to the 

 species, being strong and rapid in the Falcons, more buoyant 

 in the Harriers, light and gliding in the Hawks, heavier in the 

 Buzzards and Eagles ; but in all it is remarkably powerful. 

 They perch with ease, and when at rest on a branch or pin- 

 nacle, keep the body nearly erect, and the neck much retracted. 

 On a level surface, they incline the body forward, and draw up 

 their claws. 



These birds are for the most part solitary, and although some 

 species at times congregate when food is abundant, none of 

 those that occur in Britain are gregarious in the slightest 

 degree. Their cries are loud and shrill, with little modulation ; 

 their trachea being of nearly uniform width, its rings generally 

 cartilaginous, and the inferior laryngeal muscles reduced to a 

 single pair. They pair early in spring, and form a rude flat nest 

 of sticks, twigs, and other materials, lined with wool or hair, 

 the eggs vary from two to seven or eight, the larger species 

 having fewer than the smaller, and are of a roundish or ellip- 

 tical form. The young are at first clothed with light-coloured 

 down, and remain in the nest until fully fledged, when they 



