majority of the troop will end by being
infested. My rearing-experiments tell me much on this point. If I do
not make a careful selection when I am stocking my wire-gauze-covers,
if I go to work at random in picking the branches colonized with
larvae, I obtain very few adult Crioceres; nearly all of them are
resolved into a cloud of Midges.

If it were possible for us to wage war effectually upon an insect, I
should advise asparagus-growers to have recourse to the Tachina,
though I should cherish no illusions touching the results of the
expedient. The exclusive tastes of the insect auxiliary draw us into a
vicious circle: the remedy allays the evil, but the evil is
inseparable from the remedy. To rid ourselves of the ravages of the
asparagus-beds, we should need a great many Tachinae; and to obtain a
great many Tachinae we should first of all need a great many ravagers.
Nature's equilibrium balances things as a whole. Whenever Crioceres
abound, the Midges that reduce them arrive in numbers; when Crioceres
become rare, the Midges decrease, but are always ready to return in
masses and repress a surplus of the others during a return of
prosperity.

Under its thick mantle of ordure the grub of the Lily-beetle escapes
the troubles so fatal to its cousin of the asparagus. Strip it of its
overcoat: you will never find the terrible white specks upon its skin.
The method of preservation is most effective.

Would it not be possible to find a defensive system of equal value
without resorting to detestable filth? Yes, of course: the insect need
only house itself under a covering where there would be nothing to
fear from the Fly's eggs. This is what the Twelve-spotted Crioceris
does, occupying the same quarters as the Field Crioceris, from whom
she differs in size, being rather larger, and still more in her
costume, which is rusty red all over, with twelve black spots
distributed symmetrically on the wing-cases.

Her eggs, which are a deep olive-green and cylindrical, pointed at one
pole and squared off at the other, closely resemble those of the Field
Crioceris and, like these, usually stand up on the supporting surface,
to which they are fastened by the square end. It would be easy to
confuse the two if we had not the position which they occupy to guide
us. The Field Crioceris fastens her eggs to the leaves and the thin
sprays; the other plants them exclusively on the still green fruit of
the asparagus, globules the size of