Figs 35

le musical or stndulanng organs of the crickets are similar to those of the katydids, be.ng formed from the veins of the basal parts of the front wings. But in the crickets the organs are equally developed on each w.ng, and it looks as if these nsects could play with either wing uppermost, Yet most of them consistently keep the right wing on top and use the file of this wing and the scraper of the left, just the reverse of the custom among the katydids he front wings of male crickets are usually very broad and have the outer edges turned down in a wide flap that folds over the sides of the body when the wings are cloned. The wings of the females are simpler and usually smaller. The differences between the front w'ngs in the male and the female of one of the tree crickets (Fig- 37) is shown at B and D of Figure 33 The inner half of the wing (or the rear half when the wing is extended) ;s very large n the male (D) and has only a few veins, which brace or stiffen the wide membranous vibratory area or tympanum. The inner basal part, or anal area, of the male w: ng ,s also larger than in the female and contains a prominent vein (Cu«) which makes a sharp curve toward the edge of the wing. This vein has the stndulating file on its under surface. The veins in the wmg of an adult female (B) are comparatively simple, and those of a young female (A) are more so. But the complicated venation of the male w.ng has been developed from the simple type of the female, which is that common to insects m general. The w.ng of a young male (C) is not so different from that of a young female (A) but that the corresponding veins can be -dentified, as shown by the lettering. Taking next the wmg of the aduit male (D), it is an easy matter to determine which veins have been distorted to produce the stndulating apparatus. When the tree crickets sing they elevate the wings above the back like two broad fans (Figs. 37, 40) ana move them siaewise so that the file of the right rubs over the scraper of the left.

Fig 34, A mole cricket,

Neocurtiila hexnt'actyla

Fig 34, A mole cricket,

Neocurtiila hexnt'actyla the mole crickets

The mole crickets (Fig. 34) are solemn creatures of the earth They live like true moles in burrows underground, usually in wet fields or along streams. Lheir forefeet are broad and turned outward for digging like the front feet of moles. But the mole criekets differ from real moles in having wings, and sometimes they leave their burrows at night and fly about, being occasionally attracted to lights Their front wings are short and lie flat on the back over the base of the abdomen, but the long hind w,ng$ are folded lengthwise over the back and project beyond the tip of the body.

Notwithstanding the gloomy nature of their habitat, the male mole crickets sing. Their music, however, is solemn and monotonous, bemg always a series of loud, deep-toned chirps, like churp, churp, churp, repeated very regularly about a hundred times a minute and continued indefinitely it the singer is not disturbed. Since the notes are most frequently heard coming from a marshy field or from the edge of a stream, they might be supposed to be those of a small frog. It is Oifiicult to capture a mole cricket in the act of singing, for he is most kkely standing at a.n opening in h:s burrow into which he retreats before he is discovered.

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