76 First Report on Economic Zoology. 
Coccidcc ; the male and female scales differ in appearance and size ; 
the male scales are seldom observed. 
The female scale (Fig 8, a and b) is about one-eiglith of an inch 
long ; in form the scales are rounded behind, but taper to a point at 
one end — the head end ; they may be straight or curved, and even much 
contorted. In colour they vary from deep brown to almost grey. The 
male scale is much smaller than the female and of the form shown 
in fig. 9, c. They damage the trees by sucking out the sap by means 
of long, flexible mouths which they insert into the plant tissues. This 
scale not only occurs on the trunk and boughs of the trees, but also on 
the leaf and fruit. Foreign apples are frequently imported covered 
with this and other scale pests. The scale, as in all Coccidce , is a 
product formed by the insect which lives beneath it, partly by 
excretions from its body, partly by the cast skins of the insect, the 
so-called exuvice. 
Life-history. 
The eggs (Fig. 3, a 2 ), are laid by the sedentary female under the 
scale. They resemble to the naked eye small whitish dust. As many 
as eighty may be counted under a single scale, but the number varies 
considerably. The eggs give rise in the early summer to very small 
active six-legged larvae, which crawl from beneath the scales and 
may be distributed from tree to tree by the wind, by birds, and by 
predatory insects, such as lady-birds. They are about one-hundredth 
of an inch long. In a short time they fix themselves to the plant by 
their short proboscis and draw away the sap ; the scale then commences 
to form by the excretion of a few waxy threads and gradually grows 
to the form shown in Fig. 8. During this period the larva loses its 
legs and becomes converted into a fleshy legless creature ; the female 
remains feeding beneath the scale and is provided with a long flexible 
proboscis, which is inserted into the tissues of the plant. Towards 
the end of the summer she deposits her eggs and dies, her shrivelled 
skin remaining beneath the scale. 
If the larva is going to become a male, not only is a different 
scale produced (most often upon the leaves), but a totally different 
mature insect. The male undergoes a kind of pupal stage and 
escapes from the scale as a small winged insect, provided with two 
rather large wings and a pointed process at the end of the abdomen, 
which it can insert under the female scale and so carry out 
fertilisation. The males are very rare, most of the females reproducing 
asexually. A single brood normally exists in this country. 
