296 CORVID^. 



moult, which takes place in July. Very early in the year, 

 sometimes in January, but oftener in the next month, the 

 birds return to their nests, which are usually placed in the tops 

 of tall trees*, half a dozen or more being frequently built on 

 the same treef , but for a few weeks little is done beyond com- 

 pleting the noisy ceremonies of courtship and taking posses- 

 sion of sites. About the second week in March, the work of 

 repairing, building and furnishing is begun in earnest, and 

 is carried on amid bursts of uproar that at times arise from 

 various causes, but chiefly from attempts made by the birds 

 to rob one another of materials ; notwithstanding that while 

 a nest is in progress, one of the proprietors nearly always re- 

 mains at home to guard it, the other fetching whatever may 

 be next wanted for the structure. It has been repeatedly 

 noticed, that when a pair of Eooks attempt to build in a 

 tree previously unoccupied, and at a distance from the main 

 body, the rest often destroy the nest ; but the motive which 

 prompts these and other curious acts observable in the habits 

 of the community cannot be safely interpreted. The Rook's 

 nest is about two feet in external diameter, and is formed of 

 sticks and twigs lined with straws, grass and fibrous roots, 

 as well as wool and other soft materials. The eggs, from 

 four to six in number, are quite indistinguishable from 

 Crows', though perhaps generally rather smaller. 



During incubation, the loud disturbances that had hitherto 

 from time to time prevailed almost wholly cease, and com- 

 parative quiet reigns in the rookery. The male feeds the 

 female constantly, and occasionally takes her place on the 



* Instances however are not wanting of lower sites being chosen, especially 

 where high trees are scarce. Mr. Stevenson mentions nests in laurustinus hushes 

 and in a dwarf ilex. Mr. Cordeaux has known them in pollard willows, on an 

 apple-tree not more than seven feet from the ground and in a rough hedge. 

 At Dunij)ace, in 1878, according to Mr. Harvie Brown, some birds bred in low 

 holly-bushes, and a nest is recorded (Zool. p. 9626) which was built on the ground. 



f In some cases the number is far greater and the clusters present an extraowli- 

 nary appearance. Macgillivray mentions three trees in one rookery that bore 

 respectively twenty-six, twenty-five and twenty-three nests. In the ' Monthly 

 Magazine' (xxvii. p. 304) for April 1809 it is said that a single ash-tree, then 

 recently blown down, at Barton-on-Humber used to bear on an average one 

 hundred nests, constituting the entire rookery. 



