12 



possible, so as to facilitate comparison when making a final 

 digest. 



A close study of these routes has suggested various points 

 which, if fully confirmed, may prove of permanent value, 

 but it would be premature to publish them while they are 

 still mere theories. It would therefore be inadvisable to 

 alter the methods which we hope may lead us to a fuller 

 understanding. At the same time we would remind our 

 critics that although the routes of the different species may 

 show some apparent discrepancies from year to year, they 

 are carefully drawn up from the observations sent in, and, 

 with the commoner species at all events, accurately show the 

 area of arrival. 



We have to thank Dr. Bureau, of Nantes, for a very full 

 and detailed account of the distribution of the Yellow Wagtail 

 in France. We have not referred to it under that species as 

 it affects the general question rather than the movements in 

 any particular year, but due reference will be made to it on 

 a future occasion. 



Our thanks are also due to the Master and Elder Brethren 

 of Trinity House, as well as to all those observers and light- 

 keepers whose kindly co-operation and assistance has made 

 this investigation possible. 



F. G-. Penrose, Chairman. 



N. F. TlCEHURST. 

 C. B. TlCEHURST. 

 C. B. RlCKETT. 



J. L. Bonhote, Secretary. 



