304 Wild Life in a Southern County. 
most prominent facts in their history. It is not for 
warmth, because they pack long before it is cold. 
This summer IJ saw large flocks of starlings flying 
to their favourite firs to roost on the evening of the 
19th of June. The cuckoo was singing on the 17th, 
two days before. 
It would be interesting to know, too, whether birds 
are really as free in the choice of their mates in spring 
as at first sight appears. They return to the same 
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 members of such a gens must in that case be 
closely related. As it is not possible to identify indi- 
vidual birds, the difficulty of arriving at a clear under- 
standing is great. 
Why, again, do not robins pack? Why do not 
blackbirds, 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, standing together on a spit or sandbank. Rooks, 
