194 KEPORT — 1881. 



main body passing, and after this falls away, till the migration of that 

 species ceases or is completed. 



Independent of the normal or ordinary migration we have frequently 

 local migrations, due to sudden changes of weather, or in search of fresh 

 feeding-grounds. These ' great rushes ' of immigrants coming helter- 

 skelter on to our coasts, are, as will be seen from the Report, often accom- 

 panied, or followed very closely, with outbursts of severe weather ; and 

 a sudden increase of cold in winter will almost clear a whole district 

 of birds. 



In 1879 the maximum of immigrahts crossed the North Sea between 

 the 12th to the 2.3rd of October ; in 1880, between the 15th and end of 

 the same month ; in both years, perhaps the greatest number on any 

 given day on the 17th of the month. It is a curious fact that the 

 stomachs of migratory birds on their first landing never contain any 

 food. 



This is as much as can be set forth in an abstract. A full aiid detailed 

 account of the Migration of Birds in the Autumn of 1880, will be found 

 in the General Report, which contains much interesting matter bearing 

 on migration. It may be added finally, that in endeavouring to arrive 

 at any conclusions regarding the causes of migrational phenomena in 

 1880, as set forth in the General Report, the Committee have taken 

 more account of the vertical area of birds' flight in 1880 than in 1879, 

 and have compared the effects of prevailing north-west winds in 1879 

 pressing laterally upon the lines of migration with those of 1880, which 

 being easterly and north-easterly, have had the contrary effect of spread- 

 ing out the migratory wave, or at least not deflecting it to the same 

 extent, and also causing birds to migrate at greater elevations, and where 

 the gales have been most severe to bear them away above the range of 

 vision and carry vast numbers out to sea, until, weary and exhausted, 

 they have ceased to be able to guide themselves, and involnntai'ily 

 lowered, to be picked up senseless and stunned on board the ships, or to 

 perish in thousands in the ocean. And, lastly, the Committee have 

 hinted at the wideness of the migratory waves depending upon the 

 pressure of the starting-points, or upon, perhaps, a larger north and 

 south area occupied in the breeding season of 1880. 



The data, however, are not yet sufiicient, nor have the observations 

 been carried on sufficiently long, to ai'rive at any positive conclusions as to 

 the lioiu and the luhy of the whole matter. The Committee must, there- 

 fore, for the present, be satisfied to say nothing more, but trust that the 

 Association will enable it to continue the collection of facts. 



Report of the Committee, consisting of Lieut.-Colonel Godwin- 

 Austen, Dr. G. Hartlaub, Sir J. Hooker, Dr. Gunther, Mr. 

 Seebohm, and Mr. Sclater, appointed to take steps for investi- 

 gating the Natural Histoid of Socotra. 



The debt due to Professor Balfour for the balance of the bosts of the 



expedition (23Z. 12s. 2c?.), and the sum of Is. 3cZ. for petty expenses, have 



been paid out of the sum of 50/. gtanted at the Swansea meeting, leaving 



l).-'f c" "I 26/. 7x. 10./. in the hands of the Committee. This has been 



