PREFACE 5 
An important memoir by Mr. Guy A. K. Marshall has 
been kept back for Volume VII. In it the author advances 
many serious criticisms of the principle of Diaposematic 
Resemblance (Reciprocal Mimicry). His paper has only 
been made public, in the ‘Transactions of the Entomo- 
logical Society of London’, within the last few weeks, and 
it will be more convenient to issue it in the next volume, 
which will no doubt contain reprints of further publications 
on the same subject. 
Two interesting series of notes by Commander J. J. Walker 
on the Lepidoptera of the Dale Collection are also kept 
back, in the hope that they may be completed and issued 
as a whole in Volume VII. 
EDWARD B. POULTON: 
HOPE DEPARTMENT OF ZOOLOGY, 
UNIVERSITY MUSEUM, OXFORD, 
June 26, 1908. 
