704 



CLASS IV. INSECTA. 



Fam. 6. Mantispidae. Prothorax very long and bearing a pair of 

 raptorial legs at its anterior extremity. The four wings are sub-equal in 

 size with numerous nervures. They serve at once to distinguish this 

 family from the Mantidae, with which they have a superficial resemblance 

 chiefly owing to their raptorial front legs. The antennae are short, not 

 clubbed. The eggs are numerous and stalked ; in Mantispa styriaca they 

 are laid on stalks or stems. The larvae appear in the autumn and hiber- 

 nate till the spring, when they make their way into the egg-bags of certain 

 spiders (Lycosa) ; here they feed on the eggs and young spiders, then cast 

 their skins and turn into inert larvae, which spin cocoons inside the spider's 

 egg-cases. After a period of quiescence a nymph makes its way to the 

 outer world and soon gives origin to the imago (Fig. 449). A South 

 American species Symphrasis varia makes its home in the nests of a species 

 of wasp. A few species are found in South Europe but the majority 

 prefer a warmer climate. 



Fam. 7. Hemerobiidae. Wings at rest folded in a roof-like way over 



the body. Anten- 

 nae long, monili- 

 form or pectinated, 

 not clubbed. This 

 family is divided 

 into several small 

 groups about the 

 value and life-his- 

 tory of which there 

 is much u n c e r- 

 tainty smylus 

 chrysops, British, 

 has a semi-aquatic 

 larva which hides 

 under stones or 

 stems at the water 

 edge : it sucks the 

 juices'of Bother insects and spins a cocoon encrusted with sand, the silk 

 coming from the posterior end of the intestine which in the larva is cut 

 off from the chylific ventricle. Psectra has in the male no posterior 

 wings. The larva of Sisyra lives in the fresh water sponge Ephydatia 

 ftumatilis. The larvae of Hemerobius devour plant-lice, and those of some 

 species cover their bodies with the emptied skins of their victims. Dre- 

 panepteryx, with one British species, is remarkably moth-like and has an 

 apparatus for holding together its hind- and fore-wings as in some moths. 



Fam. 8. Chrysopidae. Long, setiform antennae, not moniliform. 

 This family includes what some writers call the " lace- wing flies," whilst 

 others call them " golden-eye flies," applying the term "lace-wing" to 

 the Hemerobiidae. They are delicate, elongate insects with a metallic 

 sheen on the living eye. Lacewings are common and there are some 

 fifteen British species. They lay peculiar stalked eggs on stems. The 

 larvae eat plant-lice and other insects. Those of some species clothe 

 themselves in the skins of their victims, which are fastened on by minute 

 hooked hairs. Green algae and lichen are attached to the body by the 

 same means. Chrysopa is a common British genus (Fig. 450). The imago 

 has a very unpleasant smell and the group is sometimes called " stink-flies." 

 Fam. 9. Coniopterygidae. Minute. Few cross-nervures on the wings, 



FlG. 450. Chrysopa flava. Cambridge. From Sharp. 



