Page:Jardine Naturalist's library Entomology.djvu/245

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PHASMIDÆ.
239

inserted before the eyes, seldom of great length, and the joints elongated. The tegmina are often wanting: when they exist they are short and narrow, never covering the hinder wings; the latter are often large, and not unfrequently ornamented with bright colours, a circumstance which generally takes place when the wings are not destined to be covered by a sheath. The prothorax is short, the body very long and linear.

These insects live exclusively on vegetable food. Their mandibles accordingly are of a different form from those of the mantidæ, and better adapted for gnawing. Like grasshoppers and locusts they lay their eggs in the earth, and for this purpose the females are provided with a small ensiform ovipositor in the extremity of the abdomen, covered by three leaflets when unemployed. The eggs of some of the species are of considerable size, certainly among the largest to be found in this class of animals. Those of Phasma dilatatum are of a slightly oblong shape, flattened on one end. They are of a brown colour and marked all over with numerous impressed points, and have on one side a mark or double waved line so disposed as to represent a kind of cross. The flattened end is surrounded by a small rim or ledge, and seems to be the part which opens for the exclusion of the larva, since it readily separates from the rest.[1]

If not the most bulky of insects, some of the

  1. Linn. Trans. iv. pl. 18. fig. 4, 5.