Democratic Sentinel, Volume 15, Number 52, Rensselaer, Jasper County, 15 January 1892 — How Insects Breathe. [ARTICLE]

How Insects Breathe.

If we take any moderately large Insect, say a wasp or a hornet, we can see, even with tho naked eye, that series of small, spot-llke marks running along the sides of the body. These apparent spots, which are eighteen or twenty in number, arc, in fact, the apertures through which air Is admitted into the system, and are generally formed in such a manner that no extraneous matter can by any possibility find entrance. Sometimes they are furnished with a pair of horny lips, which can be opened or closed at the will of the insect; in other cases they are densely fringed with stiff interlacing bristles, forming a filter which allows air, and air alone, to pass. But the apparatus, of whatever character It may be, is always so wonderfully perfect In Its action that it has been found impossible to Inject the body of a dead insect with even so subtle a medium as spirits of wine, although the subject was first immersed in the fluid and then placed beneath the receiver of an air pump. The apertures in question communicated with two large breathing tubes, which extended through the entire length of the body. From .these -main tubes were given off innumerable branches, which run in all directions, and continually divide and subdivide, until a wonderfully intricate network • r is formed, pervading every part of the structure and penetrating even to the antennae. —Great Divide.