n some are beneficial and some are destructive. In the former
group may be mentioned the Dragonflies which feed upon mosquitoes, the
Cochineal insects of Mexico, which furnish a dye-stuff, the Lady-bird
beetles, which in the larval stage feed upon plant lice; the scale
insects of India, which furnish shellac; the Bumblebees, which
cross-pollinate the clover, and the Wasps, which fertilize the figs. Dr.
Lutz says that the manna which fed the Children of Israel was honeydew
secreted by a scale insect, and that it is still eaten.

[Illustration: SEVENTEEN-YEAR CICADA OR SEVENTEEN-YEAR "LOCUST"

Range: Eastern United States. The pupa climbing tree trunk. Then it
bursts its horny outer skin and crawls out an adult.]

The Silkworm and the Honey-bee have been domesticated since prehistoric
times, the former supplying a valuable fiber for clothing and the latter
an important article of food.

Among the injurious insects a few may be mentioned: the House Fly or
Filth Fly, which may carry disease germs on its feet to the food that we
eat; the mosquitoes, which transmit yellow fever and malaria, the rat
flea, which carries bubonic plague; the weevils, which destroy rice,
beans, chestnuts, etc., and the plant lice, or aphids, which, by sucking
the juices from ornamental and food plants, are among the most
destructive of all insects.

There are so many insects in the world that we cannot hope to learn of
them all, even if we wanted to do so, but most of us wish to know the
names of those that attract our attention, and to know what they do that
is important or interesting. There are approximately 400,000 species or
kinds of insects known in the world; that is, about three times as many
as there are species or kinds of all the rest of the animals in the
world put together. This fact should not hinder us from making a start
and becoming familiar with the interesting habits of a few of the
insects about us.

The eggs of the Monarch Butterfly may be collected upon the milkweed and
brought in, so that the whole life history or metamorphosis of this
beautiful insect, from the egg through the larva or caterpillar stage
and the pupa or chrysalis stage to the adult butterfly, may be watched.
The larvae or caterpillar must be supplied daily with fresh milkweed
leaves. Other butterflies and moths and many other insects may be reared
in the same way by supplying the larvae with suitable food. If we should
find a caterpillar feeding upon t