| TWO WALKINGSTICKS |
| (Diapheromera femorata) |
The mantids—of which a common species in the Southern States is known as "mule killers" because of the superstition that its saliva poisons stock—and the gaunt "walkingstick" insects that mimic twigs so well that they are not seen as often as they might be, introduce us to the great tribe of grasshoppers or locusts—two words that it has worried bookmakers to keep straight. The grasshoppers fall into two families, distinguished among other points by the length of the antennæ. The short-horned ones (Acrididæ) are properly called locusts, and the long-horned family (Tetigonidæ) are better known as grasshoppers, despite the fact that until recently the books called this family Locustidæ. To the Acrididæ belong the locusts that in years past have worked such havoc now and then in the West, when vast swarms came from the Rocky Mountains to the new farms along the eastern border of the plains, and ate up the young grass and crops, leaving the ground looking as if swept by fire. It is a story older than written history in all plains districts of southern Asia, Asia Minor, Egypt, and northern and south-central Africa, where no earthquake, or tornado, or other reaction of nature against man's interference with natural conditions, is so dreaded as a visitation of migratory locusts. In this country any such "plagues" as half ruined Kansas forty years or so ago need no longer be anticipated, because the plowing on ranches and other disturbance of the ground in which the locusts lay their eggs is now so extensive, and the methods of checking small flocks are so well understood, that the vast surplus generations that constituted a migration in search of food in the old days are no longer born.
All the Orthoptera are musical, or at any rate noisy, and make their rattling or piercing notes as instrumentalists, not as vocalists.
"Some species," writes Frank E. Lutz, "make a rasping sound by rubbing their hind legs against their front wings (tegmina). Others rattle, while flying, their hind wings against the tegmina. These sounds are primarily amorous serenades, and Nature's serenades without attentive ears would be even more curious than the ears for which the grasshoppers perform. In this family there is an auditory organ on each side of the first abdominal segment, just above and back of the place where the large hind femora start. Notice the clear round spot on the next grasshopper you catch.... Few have not heard the masculine debates as to whether Katy did or didn't, but many do not know by sight the small, green, long-horned, stockily built disputants, both of whom usually stay high in trees. The musical apparatus of the male—the musician—is at the tegmina, and the leaflike wing covers, broadly curving entirely around the body, act as sounding boards. The female's wing covers do not have the thick rasp veins at their bases."
A third family, the Gryllidæ, contains the crickets—burrowing mole crickets, ordinary black crickets dwelling in the herbage, and several kinds of tree crickets that look like ghosts of their kind. All add to the noise of a summer evening by rubbing the roughened surface of their wing covers together—chirping to ears that are situated in the shins of the listening cricketesses.
THE TRUE BUGS
Skipping the white ants or termites, which are few and comparatively harmless in this country, but in the tropics make vast trouble for house-holders; the various sorts of lice and the little black thrips that destroys onions and some fruits, we come to the great assemblage that entomologists call "bugs," limiting the word to the order Hemiptera, which now must be considered.
The two features, basally common to all the immensely diverse members of the order, are the character of: 1. The feeding organs; and 2. The wings—in each case very distinct from that of all other insects. The bugs have highly developed piercing and sucking jaws. The mandibles and first maxillæ are transformed into stylets, often barbed toward the tip; these work to and fro within the groove of a stout-jointed beak (rostrum) which is formed by the union of the second maxillæ. The head is usually triangular in shape, as viewed from above.
As to the second characteristic, the bugs are distinguished by the modification of the fore wings into partly horny covers for the entirely membranous hinder wings. This feature divides the order into two suborders, Homoptera and Heteroptera. In the first this hardening is little evident; but in the Heteroptera—where not wingless, as in certain families—the fore wings are stiff and lie flat on the back when closed, whereas in the Homoptera they are somewhat humped over the back, and droop down on each side a little. The triangular space marked on the back by the closed wings is a ready mark by which to recognize a hemipteran, or true bug.