WINTER VISITORS 165 



like a stone and seizes its quarry in its talons ; if it 

 sees nothing it sweeps away with a few easy movements 

 of its powerful wings and hovers elsewhere. The only 

 other bird of prey that hovers hke the kestrel is the 

 black-winged kite {Elanus caerulus). This is mainly 

 white and so cannot be confounded with the kestrel. 



The explanation of the fact that one species of bird 

 of prey leaves the plains in the hot weather, while a 

 nearly related species remains, may perhaps be found 

 in the nature of their food. Birds of prey are to a 

 greater or lesser extent specialists ; while quite ready 

 to devour any small bird, reptile, or mammal which 

 comes their way, they lay themselves out more es- 

 pecially to catch one particular species, and if that 

 species migrates it follows that the bird that preys upon 

 it will also migrate. Thus the peregrine falcon lays 

 itself out to catch ducks and naturally goes with them 

 to their breeding grounds, just as the hawker of cheap 

 wares, who preys upon the mem-sahib, follows her to 

 the hills in the summer. 



In conclusion mention must be made of the Corvi 

 which visit us in winter. The arch-corvus, the grey- 

 necked rascal {Corvus splendens), of course, abides 

 with us all the year round. The raven, too, is to be 

 seen at all times of the year, but is more abimdant in 

 the cold weather than in the hot. During the summer 

 months we see comparatively few ravens ; in the winter 

 they are exceedingly numerous. Every evening 

 towards sunset a long stream of them may be observed 

 flying in a westerly direction to the common roosting 

 place. There is a similar stream of crows that flies in 



