124 PEAR. 
which I wished to secure the perfect insects. Thus the grubs were 
left undisturbed in perfectly natural circumstances, and all that was 
necessary was to look frequently when the time of development drew 
near, lest, in case of Lepidoptera (i.e. butterflies or moths), the 
specimens should have had time to injure their plumage by beating 
on the metal cover. With specimens of this nature it is well to have 
a few twigs firmly set in the ground under the dish-cover for the 
newly-developed insects to crawl up and rest on whilst spreading their 
embryo wings to full size. 
Returning to the Pear Lyda. The figure at p. 121 shows the form 
of the fly and the neuration of the two pairs of wings. The fly is four 
to five lines in length of body, that is, from a third of an inch to rather 
more ; the expanse of the wings somewhat under an inch; the colour 
chiefly black, but the abdomen tawny towards the extremity, with a 
triangular yellow mark in each segment; ventral segments banded 
with yellow. The base of the antenne and also the legs yellow; the 
four hindermost of the thighs black at base. Wings hyaline, with a 
broad smoky band below the stigma.* 
PREVENTION AND Remepres.—The simplest and most effectual plan 
would be, wherever the webs are in reach, to cut them off and destroy 
them with their contents. But a little care must be taken in order to 
secure all the caterpillars, as on alarm, when nearly full grown, they 
may let themselves down by their threads, and so escape into the 
ground. This might easily be prevented by holding a pail below the 
nest with some sticky fluid in it, soft-soap wash for instance, which 
would effectually prevent stray caterpillars getting away; and indeed 
the best method of operation would be to cut the nest itself and its 
contents off into the pail of soft-soap wash, aud thus make quite sure 
of none escaping. 
Where the nests are out of reach, syringing soft-soap or soft-soap 
and paraffin wash at them, so as to sodden the web, would be good 
treatment, taking care, as before mentioned, to have something placed 
below to secure such caterpillars as might let themselves down. 
This infestation is known as that of the Pear Sawfly, but it is also 
mischievous to the leafage of Plum and Cherry trees, and likewise to 
that of Whitethorn. 
* For description of fly (tmago) see ‘British Phytophagous Hymenoptera,’ by 
P. Cameron, vol. iii. p. 97; and for figure of fly, vol. ii. of same work, plate 6; and 
of larva, plate 12 of same volume. These figures I beg to acknowledge with thanks 
as having been copied in my own figure, p. 121. 
