244 Wild Life in a Southern County 



into the fields, and their coming back, is very striking. 

 It may possibly be connected with the phenomenon of 

 ' packing ' ; for they seem to go away by twos and threes, 

 to disappear gradually, but to retnm almost all at once, 

 and in parties or flocks. The number in the flocks varies 

 a great deal : it is a common opinion that it depends on 

 the weather, and that in hard winters, when the cold is 

 severe and prolonged, the flocks are much larger. Wood- 

 pigeons are seldom, it is said, seen in great flocks till the 

 winter is advanced. 



Has the date of the harvest any influence upon the 

 migration of birds ? The harvest in some counties is, of 

 course, much earlier than in others — a fact of which the 

 itinerant labourer takes advantage, following the wave of 

 ripening grass and corn. By the time they have mown 

 the grass or reaped the wheat, as the case may be, in one 

 county, the crops are ripe in another, to which they then 

 wend their way. 



One of the very earliest counties, perhaps, is Surrey. 

 The white bloom of the blackthorn seems to show there a 

 full fortnight earlier than it does on the same line of lati- 

 tude not many miles farther west. The almond trees ex- 

 hibit their lovely pink blossom ; the pears bloom, and pre- 

 sently the hawthorn comes out into full leaf, when a degree 

 of longitude to the west the hedges are bare and only just 

 showing a bud. Various causes probably contribute to this 

 — difference of elevation, difference of soil, and so forth. 

 Now the spring visitors— as the cuckoo, the swallow, and 

 wryneck — appear in Surrey considerably sooner than they 

 do farther west. The cuckoo is sometimes a full week 

 earlier. It would seem natural to suppose that the more 

 forward state of vegetation in that county has something 

 to do with the earlier appearance of the bird. But I 



