EAST COAST OF ENGLAND. 51 



at sea. At Heligoland, Mr. Gatke says the species is a well-known 

 customer, never in any numbers, but every spring and fall some, 

 betraying itself forthwith by its peculiar call-note, so out of all 

 proportion with its colossal beak. 



There are some birds occurring on our east coast year by 

 year with tolerable regularity, which, during the autumn of 1882, 

 have been remarkable for their scarcity. This has been the case 

 with all the large raptorial birds, and especially with the Short- 

 eared Owl, and Common Linnet and Twite. Their absence on 

 migration has also been remarked upon in Heligoland. The 

 Short-eared Owl also appears to have been specially scarce 

 on the east coast of Scotland. (See East Coast of Scotland 

 Eeport.) 



Our returns show very clearly that the spring lines of 

 migration, followed by birds leaving our shores, are identically 

 the same as those followed in the autumn, but of course in the 

 reverse direction from W. and N.W. to E. and S.E. 



As this is the fourth report issued by the Committee, we 

 may, perhaps, with the mass of facts at our disposal, be expected 

 to draw deductions, which, if they do not explain, will serve 

 at least to throw some light on the causes influencing the 

 migration of birds. We might reasonably reply that the work 

 undertaken by us was not to theorise, or attempt explanations, 

 but simply to collect facts and tabulate them. This we have 

 endeavoured to do in the shortest and simplest manner consistent 

 with accuracy of detail. There is, however, one circumstance 

 which can scarcely fail to present itself to those who have gone 

 carefully into the reports issued by the Committee, namely, the 

 marvellous persistency with which, year by year, birds follow the 

 same lines of migration when approaching or leaving our shores : 

 the constancy of these periodical phenomena is suggestive of 

 some settled principle or law governing the movement. It is 

 clearly evident, from the facts already at our disposal, that there 

 are two distinct migrations going forward at the same time ; 

 one, the ordinary flow in the spring and ebb in the autumn, 

 across the whole of the western Palaearctic regions, which of 

 course includes the British Isles, of a great migratory wave 

 moving to and from the nesting-quarters of the birds in the 

 coldest part of their range, N.E. in the spring and S.W. in the 

 autumn. Quite independent of this there is a continual stream 



