WILD LIFE IN A SOUTHERN COUNTY. 303 



places the same favourite hedge, and even the same 

 tree. Now, when the flocks split up into sections as 

 the spring draws near, each section or party seems to 

 revisit the hedge from which they departed last autumn. 

 Do they, then, intermarry year after year ? and is 

 that the reason why they return to the same locality ? 

 The fact of a pair building by chance in a certain 

 hedge is hardly enough to account for the yearly return 

 of birds to the spot. It seems more like the return of 

 a tribe or gens to its own special locality. The mem- 

 bers of such a gens must in that case be closely re- 

 lated. As it is not possible to identify individual 

 birds, the difficulty of arriving at a clear understand- 

 ing is great. 



Why, again, do not robins pack ? Why do not black- 

 birds and thrushes go in flocks ? They never merge 

 their individuality all the year round. Even herons, 

 though they fish separately, are gregarious in building, 

 and also often in a sense pack during the day, stand- 

 ing together on a spit or sandbank. Rooks, starlings, 

 wood-pigeons, fieldfares, and redwings may be seen 

 in winter all feeding in the same field, and all in large 

 flocks. 



Some evidence of a supposed tendency to intermarry 

 among birds may perhaps be deduced from the prac- 

 tice of the long-tailed titmouse. This species builds 

 a nest exactly like a hut, roof included, and in it 

 several birds lay their eggs : as many as twenty eggs 

 are sometimes found ; fourteen is a common number. 

 Here there is not only the closest relationship, but a 



