Publications of the Entomological Society of London. '753 
1879 till 1896, whenever precise information from the 
printers is not forthcoming, there is another source avail- 
able for fixing, approximately at any rate, the date of 
publication, for during this period the copies were all 
sent out from the Society’s rooms, and an exact list was 
kept of the dates on which any given part was posted. 
This sometimes serves as a useful check, and in one 
somewhat notorious case, that of Part 1 for 1894, renders 
nugatory the decree of the Society, based on the report 
of a Special Committee, that the date of the part should 
be May 11th, since the Society sent out the revised copies 
on May 2nd, and must therefore have received them by that 
date at the latest; and it is beyond the power not merely 
of a Society or its Council, but even of Omnipotence 
itself, to alter the date at which a past event has actually 
taken place. The date of this part is, however, so com- 
plicated a question that it will be best treated of in an 
appendix by itself (v. App. D). 
Since 1896 the number of pages of the Proceedings 
issued with each part of the Transactions has been 
published at the beginning of each completed volume, 
and since 1887 the part of the Transactions in which the 
Proceedings appeared is indicated at the bottom of the 
pages of the latter, but up to that time there was no 
means of dating the Proceedings except from the separate 
parts as they were issued, or from their original covers ; 
bound volumes gave no information whatever on the 
subject. I have, however, been fortunate enough to find 
the separate parts or the original covers for the most part 
in our own Library; and when they have been wanting 
there, I have found them in some cases in the British 
Museum, and in others in the Library of the Linnean 
Society. This applies to all the Proceedings published 
with the Transactions, but, unfortunately, from 1840 to 
1846 inclusive they were published in separate sheets; 
which never went through Messrs. Longmans’ hands at 
all, nor were they printed by the same firm that printed 
the Transactions, and it is these two circumstances, com- 
bined with the fact that they were sent to the Linnean 
Society with the Transactions, that enable me to assert 
that the latter Society in those days received its copies 
of our publications direct from our own rooms. The dates 
of publication of these seven years of our Proceedings 
are therefore on a totally different footing from any others, 
and must be treated of separately (v. App. 2). 
