Vlll 
PREFACE. 
Horse Forest Fly, Hippobosca equina, observations of, in a dis¬ 
trict of Glamorganshire and adjacent part of Brecknockshire, thus 
giving an additional locality of infestation to those previously recorded 
(1898, pp. 50-56). 
Pear Gnat Midge, Diplosis pyrivora .— First record of widespread 
presence in this country since first observation in the year 1888 
(1898, pp. 84-92). 
The above notes refer to only a few of the more remarkable 
infestations which were noticeable on account of their great area 
of presence; or for being previously unrecorded in this country; 
or for their great injuriousness where warmth and drought of 
longer duration than is customary here favoured insect develop¬ 
ment, and was detrimental to vegetable progress. 
Space does not allow of entering here on the great part played 
by weather influence in fostering or in checking great amount of 
insect presence; but the injurious devastations of leafage cater¬ 
pillars early in the summer of 1896 coincidently with heat and 
drought; and, on the other hand, the immense numbers of the 
caterpillars of the Silver Y-Moth which were destroyed in Essex 
in 1879 by a persistent downpour of rain in the month of August, 
are examples of two very important kinds of effects of weather 
influence. 
Reference to the Index will show many instances in which 
(especially in the case of various fruit insect pests) the various 
points of life-history have gradually been observed and recorded 
to our great benefit by scientific entomologists. 
Bird presence as an insect protection has been much entered 
on, showing the benefit in ordinary circumstances; also the 
great benefit in extraordinary amount of insect infestations of 
the extraordinary amount of birds that flock to our aid. Also 
we have record of how even where insect injury had not pre¬ 
viously been noticed as being in progress, attention has been 
helpfully directed to it by the gathering of birds to the fields. 
All kinds of birds which are even moderately insectivorous may 
be considered as helpful to an amount which makes up for 
occasional mischief (so long as they are not in overwhelming 
numbers), excepting the House Sparrow, Passer domesticus; 
but that this bird is a national evil rests on well-proved 
observations. 
Agricultural measures for lessening amount of insect pre¬ 
sence, such as in many cases can be carried out in regular 
processes of cultivation, are entered on throughout the series of 
Reports; and amongst these are especially such breakings up of 
soil as will throw out insects (surface caterpillars, for instance) 
from their self-made winter shelters to cold and wet; and also 
(on the other hand) the beneficial use of the skim-coulter in 
