WILD LIFE IN A SOUTHERN COUNTY. 175 



young return to this country with their parents after 

 the annual migration. This is particularly the case 

 after a very favourable breeding season, when more 

 than the usual proportion of young birds survive. 

 After such a season, upon returning next year to the 

 sand quarry, the older birds drive off the younger ; 

 and if these are so numerous that they cannot find 

 room in another part of the quarry, they emigrate in 

 small parties. 



I think the same thing happens with rooks. The 

 older rooks will only permit a few of their last year's 

 offspring to build near them. If a gentleman has an 

 avenue of fine elm trees in which he desires to have 

 a rookery, but cannot contrive to attract them, though 

 perhaps now and then a nest is partly built and then 

 deserted, an experiment founded on this idea might 

 be tried. It would be necessary to ask the assistance 

 of the proprietors of the nearest rookeries, and beg 

 them for one year to refrain from shooting the young 

 rooks after the well-known custom. An unusual pro- 

 portion of young birds would then survive, and next 

 building season the larger part of these would return 

 to the old trees and be immediately met in battle by 

 their older relatives. Being driven away from the 

 hereditary group of trees, they would resort to the 

 next nearest avenue or grove ; if they attempted to 

 mix with a strange tribe, they would encounter a still 

 fiercer resistance. In this way possibly the avenue 

 in question might become stocked with rooks. 



One reason, I fancy, why nests begun in such dis- 



