ON THE MIGRATION OF BIRDS. 477 
named birds are sometimes cast up dead in great numbers during the 
winter months; the result of prolonged spells of rough weather at sea, 
which render the procuring of food, and perhaps rest too, an impossibility. 
Fog.—It often happens that during an important migratory move- 
ment in the autumn or winter, fog prevails. On such occasions more 
birds than usual approach the lanterns of the light-stations and are 
killed, sometimes in considerable numbers, by striking against the giass. 
This phenomenon is another effect of those anticyclonic spells which 
have been mentioned as favourable to and causing emigration, and it is 
thus not surprising that the birds should encounter foggy weather 
during their movements. Such atmospheric conditions are well known to 
meteorologists to be characteristic of these high-pressure systems, and of 
their frosty periods, which latter are also the chief cause of the winter 
movements. 
There is also some direct evidence that birds lose themselves in foggy 
weather, since practically non-migratory species, such as Sparrows, appear 
during its prevalence at unusual seasons at stations just off the coast. 
CoNCLUSION. 
In conclusion it remains to be stated that this is merely a Sum- 
mary of the Results obtained from a careful study of the data. It is 
not claimed for the Digest that it is exhaustive in any department. 
Indeed, such is far from being the case, and it is recognised that much yet 
remains to be extracted from the enormous mass of information now 
reduced to order. Further research will, no doubt, yield results of a 
useful, if not an important nature. 
It has been found impossible here to enter into many interesting 
details in connection with the facts now established, while a vast amount 
of useful information of a statistical nature awaits publication. Much of 
the latter, however, can only be treated of under the numerous species to 
which it relates. 
To the further consideration of the data, with a view to obtaining 
possible new and interesting facts, I am still actively devoting my atten- 
tion. I trust in due course to make a more detailed and supplementary 
communication on Bird-migration in the British Islands, and on the inter- 
relationship existing between it and the various other phenomena with 
which it is associated. 
Post Office Regulations regarding the Carriage of Natural History 
Specimens to Foreign Countries.—Report of the Committee, consist- 
ing of Lord WatstncHaM (Chairman), Mr.. R. McLacutuan, 
Dr. C. W. Stites, Colonel C. SwinHor, and Dr. H. O. Forses 
_ (Secretary). 
Your Committee have to report that they have been in communication 
with the Postmaster-General in reference to the object for which they 
were appointed, namely, to obtain from the Post Office the relaxation of 
the rule which prevents small parcels of natural history objects, sent for 
purely scientific purposes, from passing through the post to addresses 
abroad at sample-post rates, a privilege enjoyed by the Continental natu- 
ralists when transmitting to England. Your Committee regret that the 
latest reply from his Grace leaves no immediate hope of obtaining this 
concession, and they therefore do not ask for reappointment. 
