10 
the winter, it is well to gain reliable information on this 
point before beginning operations. 
It may seem almost idle to offer such a suggestion, but 
sometimes great expense is gone to in applying what are 
known to be insect-deterrents, but which fail in their 
effect because no insect is there to be acted on; and the 
landholder not only loses by the unprofitable outlay, but 
is discouraged from further trial. 
Eggs .—The effect of weather as a means of destroy¬ 
ing insect-eggs appears to depend on their being exposed 
to weather influences of a different kind to those they 
were prepared for by the arrangements of the parent 
insects, or by their own special constitutions. Thus in 
the case of the Aletia argillacea —the moth of which the 
eggs produce the well-known cotton caterpillars of the 
United States—we are told that these eggs are laid 
during the summer beneath the leaves, or exceptionally 
on the leaves, or on any exposed part of the plant, but 
“ all eggs perish which are unhatched when overtaken 
by frost.”—(Cotton-worm Bulletin, p. 10). 
Some eggs are destroyed by heavy rain, but the 
weather influence, that seems mainly to be depended on 
as an agent, we can fairly bring to bear in agricultural 
practice, is desiccation, that is, drying the egg by throw¬ 
ing it out from its natural locality to such influence of 
air and sunshine as may dry up the contained fluid, and 
thus prevent the embryo within from developing. 
In many cases the egg, whether laid singly or in 
clusters, is so placed as to be protected from rapid dry¬ 
ing or sudden changes of temperature. This locality is 
often either a little below the surface of the ground, as 
with one or more of the Onion Flies, the Carrot Fly, 
Cabbage-root Flies, and others, or amongst damp her¬ 
bage, or on, or close to, the plants at the ground level, as 
with the Daddy Longlegs or the Click Beetle (from whose 
eggs we are infested with the Wireworm); and many 
moths lay similarly. Some eggs, as of the Turnip 
Flea-beetle, the Beet Fly, and the Large Cabbage 
Butterfly, are laid on the under side of the leaves, and 
