554 BRITISH BIRDS. 



and to be compelled to seek refuge elsewhere. But at last their caws are 

 heard in lessening numbers ; and finally all is silent. 



"When the young are able to fly, the whole colony, both young and old, 

 frequently soar to an immense height directly above the nest-trees, and 

 wheel round and round in circles, ever and anon buffeting each other. 

 Then, when anxious to alight, they often perform the motion known to 

 country-people as " shooting/-" coming down with great rapidity on wings 

 a little raised and in a zigzag direction. To see a large number of Rooks 

 so engaged is indeed a grand sight. By many people this peculiar flight 

 is thought to portend wind ; but it is merely the birds' mode of alighting 

 on ground or trees directly beneath them. As a rule the Rook alights 

 more slowly and warily, and often passes and repasses over the same 

 ground. 



Like most other species of the Crow tribe, Rooks are almost omni- 

 vorous. They are very fond of picking a bone, if they can get the 

 chance. In autumn they vary their fare with acorns, which they obtain 

 very often by flying up to the slender twigs and breaking them off by 

 their own weight, hanging suspended from them. Of their propensity 

 for egg-stealing little need be said. That they will sometimes despoil a 

 nest cannot be denied; but such cases are very exceptional. They have 

 also been said to feed on small birds and mammals. Rooks often frequent 

 the sea-coast in search of the numerous animal substances to be found 

 there. Sometimes they may be seen preying upon mussels, obtaining the 

 mollusk by carrying the shell up to some considerable height and dropping 

 it on a rock or stone, just as the Crows do. Fruits of various kinds also 

 form part of their diet, as well as beech-nuts and berries. Although a 

 rookery is not to be encouraged in the neighbourhood of a Grouse-moor, 

 we have no bird of greater use to the agriculturist ; and its few little 

 failings are amply repaid by its countless good offices in ridding fields 

 and pastures of some of their greatest pests. 



Much controversy has taken place, and considerable diversity of opinion 

 exists, as to the nature of the bare patch at the base of the mandibles of 

 the Rook. That this bareness is produced by the bird rubbing off its 

 feathers when digging in search of food is impossible ; for if such were 

 really the case, why should not the Carrion-Crow, the Jackdaw in fact, 

 all others of its kindred exhibit a similar peculiarity ? for all dig just as 

 much. There can be but little doubt that these small feathers drop off 

 a peculiarity which began in some remote ancestor of the Rook and, 

 proving to the advantage of the species, was developed by natural 

 selection. 



The Rook has the entire plumage black, beautifully glossed, especially 

 on the upper' parts, with rich bluish purple, especially on the head and 

 neck. At the base of both mandibles, and extending some way down the 



