What are Insects?
Insects Home
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In most cases the parent insect deposits small eggs which hatch later into the young
insects. In some cases, as
with the blow-flies, the maggot may hatch from the egg while yet in the parent's body, when the active larva is born
alive. Whether the egg hatches before or after it is deposited, the young insect continues to develop in one of three
ways. It may resemble the parent and simply grow as does a kitten, or it may look somewhat like its parent though
smaller and without wings, as the young
grasshopper, or it may bear no resemblance whatever to the parent, as
caterpillar which feeds and grows and finally spins a cocoon in which it passes to the resting chrysalis stage
and later emerges with wings. The development of
insects is therefore extremely complicated.

In order to study a group of animals which includes so many thousand different kinds it is necessary to divide
them into a number of sharply defined divisions or orders. All animal life is naturally grouped into such divisions
and subdivisions. Among the
insects we at once detect seven large, sharply defined divisions or orders, and ten
or more smaller ones. Of these we have first, the two-winged true flies; second, the four-winged
butterflies and
moths; third, the hard-backed
beetles; fourth, the stinging four-winged wasps and bees; fifth, the variously formed
sucking insects or true bugs, as chinch bugs and bed-bugs; sixth, the rapid-flying four-winged snake doctors or
dragonflies and, seventh, the hopping forms, the grasshoppers. Besides these we have the various smaller
orders of water-loving insects,
fleas, etc. The seven groups mentioned above include the majority of our common
forms and in the studies to follow we will include only representatives from these orders.

Their Habits
The habits of insects are as varied as their forms and adaptations. Some live in the water all their life, others
spend a part of their life under water, others live the care-free life of the open air, others enjoy feeding upon and
living in the foulest of filth, others associate themselves with certain definite crops or animals thereby doing untold
injury, while others produce food and other materials which are to be used by man for his comfort. Every
imaginable nook and crook, from the depths of lakes to the tops of mountains, from the warm, sunny south to the
cold frigid north, from the foul damp swamps to the heart of our desert lands, offers a home for some small insect.

The most striking habits and developments among insects is found in the more highly advanced families of
ants where definite insect societies are formed, resembling in many respects human societies and human
activities. Among these villages are established, homes built, battles fought, slaves made, herds kept by
shepherds, and even fields cultivated. In these groups we have the nearest approach to human intelligence.

Their Role in Agriculture
Some insects may be very destructive to crops, others are beneficial, while the majority of insects are of no
importance to man or agriculture. The various forms of pests such as the chinch bug,
potato beetles, and others
do an enormous amount of damage each year. They destroy hundreds of millions of dollars' worth of crops
annually in the United States alone. They devour enough to pay for the entire cost of running the school system of
the USA and nearly enough to meet all the expenses of the US Government. In view of these facts it is the duty of
each and every farmer, young or old, to acquaint himself with these destructive pests and prepare himself for
combating them. With a knowledge of the methods of controlling these pests much of this enormous loss can be

While some insects are extremely injurious, others are very helpful. The products of the honey
bee in the United
States alone amount to several million dollars a year, to say nothing of its value to the farmer in pollinating fruits.
The annual output of silk, all of which is spun by the silkworm, is worth millions of dollars. Many other forms are of
value to man by producing material of commercial value such as lac, shellack, dyes, medicines, etc. Of all the
beneficial insects those which are of greatest value to man are the parasites and similar forms which help to keep
in check many of  the severest pests of the farm. Insects are not all bad fellows by any means. One must acquaint
himself with those which are good and those which are bad before he can hope to deal with them intelligently.

"And with childlike credulous affection, We behold those tender wings expand, Emblems of our own great
resurrection, Emblems of the bright and better land."  ~LONGFELLOW.

◄◄Insects Home
The chinch bug showing development with incomplete
metamorphosis; a, egg; b, first nymph; c, second nymph;
d, third nymph; e, fourth nymph; f, adult winged bug; g,
chinch bugs extracting sap from corn plant. To control
this pest burn over all winter harboring places and use
chemical or dust barriers following wheat harvest.
The Principal Orders►►
The Hessian fly showing development with complete
metamorphosis; a, egg; b, larva or maggot; c, flax-seed
stage; d, pupa; e, adult winged fly; f, wheat stubble
with flax-seed stages near base taken after harvest. To
control this pest, plough under stubble after harvest;
keep down all volunteer wheat and sow wheat after
fly-free date in the fall.►►
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