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False Rear-horses

(Family Mantispidae.)

As the name would indicate, these insects bear some resemblance to the Mantidae, or praying Mantes, or "rear-horses" as they are called in the South. They have a long neck, and the strong, dilated and spined front legs are inserted just behind the head, and are used for capturing their prey.

Very few species inhabit the United States, only two, Mantispa brunnea and M. interrupta, having a very wide distribution.

The transformations of these creatures was for a long time a mystery, but Brauer, of Vienna, learned about thirty years ago that they live upon the eggs and young of spiders. Their eggs are very small, and very numerous, and each is placed at the tip of a long stalk, very much the same way as are the eggs of the lace-winged flies which will be described later. The eggs are laid in the fall and the larvae hatch before winter, but remain hidden without food, until spring. Then they search for the egg cocoons of certain spiders, pierce them, and enter among the eggs. When the eggs are nearly ready to hatch they eat them and the young spiders as well, until they are full grown, molting only twice, and the changing to pupae or nymphs within the larval skin. Just as in the last family, the pupa is active before giving out the fly, and works its way through the larval skin, through the egg cocoon of the spider, and gives forth the adult.

In the genus Symphasis, which belongs to this family, the transformations of our single native species, which lives in California, have not been studied, but a South American species lives in the nests of a wasp.