240 BRITAIN^S BIRDS AND THEIR NESTS. 



nest itself is a pile of twigs, often of absurdly large 

 dimensions, as the smoke-filled rooms of many an old 

 house testify. A lining of wool or other material is added, 

 and the Daw's propensity for bearing to its nest bright 

 but useless articles is proverbial, and has formed the key 

 to the plot of many a tale. The four to six eggs, laid 

 late in April, vary from pale blmsh green to grayish white 

 in ground-colour, and the markings are more definite in 

 shape and darker in hue, as a rule, than those on the 

 eggs of the other typical Crows. 



THE ROOK 



(Corvus frugilegus). 

 Plate 75. 



Over the greater part of the British Isles the Rook 

 is by far the most abundant and familiar kind of Crow, 

 and it is to this species that the loosely used popular 

 name * Crow ' is most frequently applied. Not only is it 

 very common, by no means avoiding the neighbourhood of 

 human habitations, but it is also conspicuous because 

 of its very markedly gregarious habits, and the amount 

 of noise which always exists to remind the landowner of 

 ' the black republic in his elms.' 



Being a strictly arboreal species, the Rook naturally 

 becomes less common in the extreme north of Scotland ; but 

 there it has of late been extending its range. Through- 

 out the rest of our area it is almost ubiquitous, but it 

 is rather more abundant in the north of England than 

 in the south. Its British migrations correspond closely 

 with those already described for the Jackdaw. 



The nesting habits of a single pair of Rooks closely 

 resemble those of a pair of Carrion -Crows who have 



