BRITAIN'S BIRDS AND THEIR NESTS. 241 



chosen a tree-site. The nest, rarely wool -lined, is of 

 the same type. Non-arboreal sites are exceptional. The 

 three to five eggs are very similar to those of the Carrion- 

 Crow, but rather smaller. The young may always be 

 distinguished by the colour of the inside of the mouth — 

 dark flesh -colour at first, becoming slaty, whereas it is 

 always pale flesh-colour in the Carrion-Crow. 



The full-grown birds of the two species differ in many 

 ways. Most obvious is the bare white patch on the 

 Rook's ' cheeks.'' This, however, is feathered till after the 

 second moult. The Rook is built on more graceful lines 

 than the Crow ; the flight is lighter ; the voice is much 

 less harsh. 



But the most distinctive feature of both the nesting 

 and the general economy of the Rook is, of course, 

 its gregariousness. Its social organisation has appai'ently 

 reached a higher level than among any other species of 

 birds, but does not appear to have received the attention 

 it deserves. Accounts there are without number of Rook 

 ' trials "* and what not, but such descriptions as we have 

 seen have been so overlaid with fantastic interpretations 

 as to be rendered almost worthless. In the apparent 

 absence of serious scientific study of the subject we feel 

 that it would be unprofitable to attempt any discussion. 



THE MAGPIE 



(Pica rustica). 



Plate 76. 



As we have already said. Crows have been held from 

 antiquity to be birds of good or evil omen, according to 

 the circumstances of their appearance, and in the primitive 

 augury of our superstitious peasantry the present species 



2 E 



