20 INSECTS NOXIOUS TO AGRICULTURE. 
duce young is perhaps one of the most mysterious things in 
Nature. The male of Mytilaspis pomorum has never been found 
in New Zealand or Europe, and doubtfully in America. 
Lecanium hesperidum has been known and studied for nearly two 
hundred years without any male, pupa or adult, being discovered. 
Yet both of these species go on increasing regularly and in great 
numbers, and show no signs of extinction. 
In spite of this absence of males in some cases, and of the 
comparatively small numbers of eggs, Coccids would naturally in- 
crease at an exceedingly rapid rate if left undisturbed, on account 
of the great proportion of females. They are, moreover, pro- 
tected, to a great extent—First, by the fact that birds do not, as 
a rule, care to eat them. The “ blight-bird ” or “ white-eye,” 
Zosterops lateralis, has been noticed in this country pecking about 
in holly-hedges infested by Lecaniwm hesperidum; but it is not 
absolutely certain whether it was eating the Coccids or the other 
more easily picked-off insects on the plant, such as Psocus, which 
is very commonly observed among Coccids. And other birds 
seem not to devour them at all. Secondly, the usual position of 
these insects, on the under side of the leaves, or in the crevices 
of bark, is a great shelter and protection for them against birds 
or ordinary accidents. Again, they are in many cases effectu- 
ally covered by the waxy or fibrous shields, or by the masses of 
eotton with which they surround themselves. In countries like 
the South of France, California, or the greater part of New Zea- 
land, the winters do not appear to be sufficiently severe to injure 
Coccids, and many of them breed as much in winter as they do 
in summer. It would therefore seem that everything combines 
to assist these msects in their career, and in their propagation. 
Nature, however, has provided a check which is to some extent 
effective, at least against several species, although, unhappily, 
against some of the most noxious—such as Mytilaspis pomorum, 
the Dactylopii (mealy bugs), Icerya purchasi, &e.—it is not 
energetic im this country; and this remedy is the attacks of other 
minute animals, whether by direct devouring of the Coccids or 
by parasitism. 
Direct attacks from animal enemies are not frequent. 
Whether from some inherent distastefulness, or from the diffi- 
culty of getting at them, Coccids are scarcely subject to being 
directly devoured. There are a few exceptions. Under the 
puparia of Mytilaspis pomorum a minute white Acarus (mite) 
