328 Professor E. B. Poulton on 
Mr. G. A. K. Marshall joined in the work, and after a time 
convinced me that it would be better to defer the records 
of predaceous Hymenoptera to a second part. So much 
has been done that the paper would appear to be a com- 
plete abstract of literature bearing on the subject ; and if it 
failed to be truly complete great harm would be done; for 
the way toan adequate statement would certainly be barred 
for many years to come. It was therefore determined to 
put off the appearance of Part II, devoted to the predaceous 
Hymenoptera, until the abstract of published records is as 
fulland complete as itcan be made. It is believed that the 
work will be finished early in 1907, and that no long interval 
need elapse between the two sections of the memoir. 
The same argument does not apply to the First Part, 
which is in the main a presentation of new records, and 
does not profess to contain anything like a complete 
abstract of the published records scattered chiefly in the 
form of brief notes, though a voluminous literature. At 
the same time any published statements which have come 
to light are included; and many more will certainly be 
found in the systematic search for records of predaceous 
Hymenoptera. Any such additions to Part I will appear 
in the form of an Appendix at the end of Part II. 
I desire to thank the Council for their courtesy in 
permitting, as an exceptional privilege, the inclusion of 
predaceous insects and their prey captured after the date at 
which the paper was read,—June 6th, 1906. All such addi- 
tions will be immediately recognized by their dates. Owing 
to this concession many of the conclusions rest upon a far 
broader foundation than would otherwise have been possible. 
It is hoped that this paper will be of some use to those 
who are interested in the problems of Economic Entomology 
rather than in the study of Insect natural history or bio- 
nomics for their own sake. With this object the popular 
names have been used whenever possible, and the classifica- 
tory position of the prey indicated. I have been much im- 
pressed with the imperative necessity for the accumulation 
on a very large scale of this kind of evidence, if trustworthy 
conclusions are to be reached—conclusions safe enough to 
become the justification for practical measures. It is not 
sufficient to know that an insect is predaceous, and that it 
is believed in a general way to attack particular species or 
groups of species. We need precise records and the care- 
ful preservation of material for critical examination in the 
future. Thus it will be found in numbers of cases that 
