The Bush Crickets

The bush cri ;kets d ffer from the other crickets in having the middle joint in the foot larger and shaped more like the third joint in the foot of a katydid (Fig. 17 B). Among the bush crickets there ,s one notable singer common in the neighborhood of Washington. This is the jumping bush cricket, Orocharis saltator (Fig. 42), whc comes on the stage late in the season, about the middle of August, or shortly after. Hi s notes are loud, clear, piping chirps with a rising inflection toward the end, suggestive of the notes of a small tree toad, and they at once striKe the listener as something new and different in the insect program. The players, however, are at first very hard to locate, for thev do not perform continuously —one note seems to come from here, a second from over there, and a third from a different angle, so that it is almost 'impossible to place any one of them. But after a week or so the ciick-ets become more numerous and each player more persistent till soon their notes are the predominant sounds in the nightly concerts, standing out lcud and clear against the whole tree-cricket chorus. As Ruey says, this chirp is so distinctive that when once studied it is never lost amid the louder racket of the katydids and other night choristers "

After the first of September i* is not hard to locate one of the performers, and when discovered with a flashlight, he is found to be a medium-s'zed, brown, short-legged cricket, built somewhat nn the style of Gry 11 us but smaller (Fig. 42). The male, however, while singing raises his wings straight up, after the manner of the tree crickets, and he too, carries a basm of liquid on his back much sought after

Fio 42. The lump.ng bush ci.cket, Oroihans saltator

Upper figure, a male lower, a female

Fio 42. The lump.ng bush ci.cket, Oroihans saltator

Upper figure, a male lower, a female by the female In fact the iqu;d is so attractive to her that, at least 111 a cage, she is sometimes so persistent in her efforts to obtain it chat the male is clearly annoyed and tries to avoid her. One male was observed to say very distinctly by his actions, as he repeatedly tried to escape the nibbling of a female, presumably his wire since she was taken with mm when captured, I do wish you would quit pestering me and let me sing! Here is another piece of evidence suggesting that the male cricket sings to express his own emotions, whatever they may be, and not primarily to attract the female But if, as in the case of the tree crickets, his music tells the female where she may find her favorite confection, and this .n turn leads to matrimony, when the male is in the proper mcod. it suggests a practical use and a reason for the stridulatng apparatus and the song of the male insect.

Walking-Sticks and Leaf Insects

Talent often seems to run in families, or in related families, but it does not necessai'ily express itself in the same way. If the katydids and crickets are ncted musicians, some of their relatives, belonging to the family Phasmidae, are incomparable mimics. Their mimicry, however, is not a conscious imitation, but is one bred in their bodily forms through a long line of ancestors

Fin 43 The common wa!knig-stick insect, Viajiheromera / emcrata, of the eas tern pari of the United States. (Length iyi inches)

If sometime in the woods you should chance to see a short, slender puce of twig suddenly come to life and slowly walk away on iix slim legs, the marvel would not be a miracle, but a walking-stick insect (Fig 43). These insects are fairly common in the eastern parts of the United States, but on account of their resemblance to twigs, and their habit of remaining perfectly quiet for a long time with the body pressed close to a branch of a tree, they are more frequently overlooked chan seen. Sometimes, however, they occur locally in great numbers It is supposed that the stick insects so closely resemble twigs for the purpose of protection from their enemies, but it has not been shown just what enemies they avoid by their elusive shape The stick insects are more common in the South and in tropical countries, where some attain a remarkable length, one species from Africa, for example, being eleven inches long when full-grown In New Guinea there lives a species that looks more like a small club than a stick, it being a large, heavy-bodied, spmy creature, nearly six mches in length and an inch in width through the thick est part of its body (Fig. 44).

Other members of the phasmid family have specialised on im.-tating leaves. These insects have wings in the adult stage, and, of course, the wings make 't easier for

Fic. 44. A gigantic spiny waiking-etick insect, Eury-•anthus horr.Ja from New Guinea. (Length 5K inches)

them to take the form of leaves. One famous species that lives in the East Indies looks so much like two leaves stuck together that it's truly marvelous that an insect could be so fashioned (Fig. 45). The whole body is flat, and about three inches long, the bases of the legs are broad and rregu-larlv notched, the abdomen is spread out almost as thin as a real leaf, and the leafliice wings are held close above it. Finally, the color, which is leaf-green or brown, gives the last touch necessary for complete dissimulation.

The Mantids

It is often observed that genius may be perverted, or put to evil purposes. Here is a family of 'nsects, the Man-ndae, related to the grasshoppers, katydids, and c ick-ets, the members of which are clever enough, but are deceitful and malicious.

■ he praying mantis, Stagmomantu Carolina (Fig. 46), though he may go by the aliases of rear-horse" and soothsayer," gets his more common name from the prayerful attitude he commonly assumes when at rest.

Ahe long, necklike prothorax, supporting the small head, is elevated and the front legs are meekly folded. But if you examine closely one of these folded legs you Will see that the second and third parts are armed with suspicious-looking spikes, which are concealed when the two parts are closed upon each other. In truth, the mantis is an arch hypocrite, and his devotional attitude and meek looks betoken no humil ty of sp r't. The spiny arms,

fio. 45 A tropical leaf insect, Pulchriphvlhum pulchriiolium, a member of the walking-stick fam ily. (Length 3 inches)

so innocently folded upon the breast, are direful weapons held ready to strike as soon as some unsuspecting insect happens within their reach. Let a small grasshopper come near the posing saint: immediately a sly tilt of the head belies the suppliant manner, the crafty eyes leer upon the approaching insect, losing no detail of his movements. Then, suddenly, without warning, the praying mantis becomes a demon in action. With a nice calculation of distance, a swift movement, a snatch of the

Fic. 46. The praying mantis, Stagmomantis Carolina, and remains of its last meal. (Length 2K inches)

terrible clasps, the unlucky grasshopper is a doomed captive, as securely held as if a steel trap had closed upon his body. As the hapless creature kicks and wrestles, the jaws of the captor sink into the back of his head, evidently in search of the brain; and hardly do his weakening struggles cease before the victim is devoured. Legs, wings, and other fragments unsuitable to the taste of an epicure are thrown aside, when once more the mantis sinks into repose, piously folds his arms, and meekly awaits the chance arri/al of the next course in his ever unfinished banquet of living fare

Some exotic species of mantids have the sides of the prothcrax extended to form a wide shield (Fig. 47), beneath which the forelegs are folded and completely hidden It is not clear what advantage they derive from this device, but it seems to be one more expression of decei :.

Of course, as we shall take occasion to observe later, goodness and badness are largely matters of relativity

Fig. 47. i mantis from Ecuador with a shieldlike extension of its back. '.Length 3y% inches)

Fic. 48. Egg cafe of a mantis attached to a twig, Stagmcmanus

Carolina

Fic. 48. Egg cafe of a mantis attached to a twig, Stagmcmanus

Carolina ihe mantis is an evil creature from the standpoint of a grasshopper, but he would be regarded as a benefactor by those who have a grudge against grasshoppers or against other insects that the mantis destroys. He nee, we must reckon the mantis as at least a beneficial insect relative to human welfare. A large species of mantis, introduced a few years ago into the eastern States from China, :s now regarded as a valuable agricultural asset because of the number of harmful insects it destroys.

The mantids lay their eggs in large cases stuck to the twigs of trees (Fig. 48). The substance of which the case is made is similar to that with which the locusts inclose their eggs, and is exuded from the body of the female mantis when the eggs are laid. 'he young mantids are active little creatures, without wings but with long legs, ana it is the fate of those unprotected green bugs, the aphids, or plant lice, that infest the leaves of almost all kinds of plants, to become the puncipal victims of their youthful appetites.

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