St. Nicholas/Volume 32/Number 1/Nature and Science/How Insects Breathe

How Insects Breathe.

Insects cannot breathe through their mouths as can most of the higher forms of animal life, nor do they have their breathing-openings near the mouth.

The early part of the insects’ lives is chiefly spent in eating, and their mouths are so largely

The “Nostrils"— The breathing holes on the side of a cricket.

engaged in this work that it would not be possible to use them also for breathing; while to have their nostrils in the immediate vicinity of their mouths would be very inconvenient. They must therefore be supplied with air in some other way.

The breathing apparatus of an insect
(Spiracle and trachea).Accordingly Mother Nature has little breathing-openings on the various segments of which their bodies consist. Scientists call these openings spiracles, Hold a locust between your fingers and watch the breathing movements of the body. Professor Packard says: “There were sixty-five contractions in a minute in a locust which had been held between the fingers about ten minutes.” How does that compare with the number of breaths you take each minute? Insects of swiftest fight breathe most rapidly.

Each spiracle is guarded by little projecting spines which form a latticework or grate to keep out dust, etc. After passing through the spiracle the air is conducted to all parts of the body by tubes made by tiny spiral threads, This microscopic tube is something similar in form to a curl of hair made by brushing the hair around a curling-stick and then pulling out the stick.