1897- THE MIGRATION OF BRITISH BIRDS. 251 



Some interesting facts are to be gleaned from the records of these 

 spring arrivals. Thus, it is found that the earhest arrivals appear in 

 the south-western, that is, in the warmest section of the British area ; 

 also that the earliest arrivals amongst the summer visitors are those 

 individuals of the species with more extended range which stay to 

 breed in Britain ; this is exempUfied by the snipe, some of which are 

 already breeding in this country before the more northerly breeding 

 birds of the same species have all passed on ; the same may be said 

 of the great crested grebe. Other observations are quoted in proof 

 that the migrants bound for the far north are the last of their kind to 

 appear in the British area. 



During all this time the corresponding spring Emigration is going 

 on, and those birds which have wintered with us are leaving for their 

 summer haunts. In February the geese begin their northern move- 

 ments, and larks and rooks are proceeding to the Continent by the 

 east and west route. In March the northerly current becomes more 

 pronounced, shore-larks, geese, ducks and divers taking their 

 departure, and the Continental outpour gains in intensity. In April 

 no less than thirty-four species which have wintered with us are 

 recorded as departing for their northern summer haunts, and the final 

 departures by the east and west route take place. May sees the 

 maximum amount of emigration to the northern breeding grounds, 

 both of species which have wintered with us and of birds of passage. 

 Fifty-three species of regular emigrants are recorded for this month, 

 but it may be the middle of June or even later before the last of the 

 Polar breeding birds have taken their departure. It is noteworthy 

 that this great stream of migrants passing to the north-east, as well 

 as the exodus by the east and west route, each takes place from its 

 allotted section of the eastern coast, " a few only of the species, such 

 as the redwing, wheatear, white wagtail, barnacle goose, swans, 

 whimbrels, etc., passing up our western coasts, possibly en route for 

 Iceland." 



There remains one other important section of the " Digest " to 

 notice, that is the one devoted to Meteorology, and for the purpose 

 of establishing " the actual relationships between migratorial and 

 meteorological phenomena." The material at the disposal of the 

 committee is said to be both extensive and reliable, the " Daily 

 Weather Reports," based upon observations made at fifty-four widely- 

 distributed stations, and issued by the Meteorological Office, having 

 been used. As Mr. Clarke explains at length, migration is con- 

 trolled, if at all, by meteorological conditions obtaining in the region 

 from which the birds are starting, and obviously not by those in the 

 region to which they are going. Thus, British immigrants are 

 affected by Continental conditions, and British emigrants by our 

 home conditions. " As a result of an extensive series of comparisons 

 instituted between the two sets of phenomena, it has been ascertained 



that they are most intimately associated, and that a knowledge of the 



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