"Suborder TRICHOPTERA ([Greek: thrix], hair; [Greek: pteron], wing), or Caddis-flies, containing the single family Phryganeidae, and placed with the Neuroptera, though bearing great affinities with the Lepidoptera. Every good disciple of Walton and lover of the "gentle art" knows the value of the Caddis-fly, or Water-moth, as bait. These flies very much resemble certain small moths, the scales on the wings of the latter being replaced in the former with simple hairs. The larvae live in the water and inhabit silken cases, which are usually cylindrical and covered with various substances, according to the species, or the material most conveniently obtained by the individual." Suborder MECOPTERA ([Greek: mekos], length; [Greek: pteron], wing). This suborder includes a peculiar group of insects, the most striking characteristics of which are the mouth-parts, which are prolonged into a rostrum or beak. The wings are long and narrow, and of nearly equal size. The abdomen of the male is constricted near its posterior end and terminates in long clasping organs from which these insects obtain the common name of Scorpion-flies. [Illustration: FIG. 35.--Panorpa or Scorpion-fly. (From Packard.)] The larvae of one genus (_Panorpa_) are remarkable for their great resemblance to the larvae of Lepidoptera. They have, however, eight pairs of abdominal legs. The habits of these insects are not well known, but they are supposed to be generally. Suborder NEUROPTERA. This group as restricted by modern authors is a small one, including the largest species, as in the Hellgrammite, the Lace-wing Flies, the Ant-lions, and the Mantispas representing the families, Sialidae and Hemerobiidae, with their subfamilies. The first includes the so-called Hellgrammite Fly (_Corydalus cornutus_), one of our largest and most striking insects, the larvae of which is known as Dobsons by anglers, and is aquatic and carnivorous in habit. The Hemerobiidae is a large family, comprising, as a rule, delicate insects with rather ample gauzy wings. The larvae are predaceous. The common Lace-wing flies are among our most beneficial insects, destroying plant-lice and other soft-bodied species. To the same family belongs the Ant-lion (_Myrmeleon_), the larvae of which have the curious habit of constructing a funnel-shaped burrow in the sand, in the bottom of which they conceal themselves and wait for any soft-bodied insects which may fall into the trap. This family also includes the peculiar Mantis-like insects belonging to the genus _Mantispa_. As in the true Mantis, the prothorax of these insects is greatly elongated and the first pair of legs are fitted for grasping. The larvae are parasitic in the egg-sacs of certain large spiders (genera _Licosa_, _Dolomedes_, etc.), and undergo a remarkable change in form after the first molt. In the first stage the larvae are very agile, with slender bodies and long legs. After molting