594 



INSECTA. 



Bub-order 1. Terebrantia. 



Female with ovipositor as tube or borer (terebra), which projects 

 freely at the end of the abdomen, and is sometimes retractile. 



Tribe 1. Phytophaga. Abdomen sessile. Trochanter composed 

 of two rings. Larvae phytophagous, resemble caterpillars. 



Fam. Tenthredinidae (Leaf- wasps). Saw-flies. Abdomen sessile with short 

 borer. The larvie have rarely three, usually nine to eleven pairs of legs, 

 and resemble caterpillars. The females lay their eggs in the epidermis of 

 leaves, the puncture causes the flow of .sap. which the egg imbibes and thereby 

 increases in size. The young larvae feed on leaves, often in early stages live 

 in societies, and become pupae in a cocoon. They are distinguished from 

 the caterpillars by the greater number of legs, and by the two ocelli on 

 the horny head. Lyda betulee L.. Tenthrcdo (Atlialia) sphw.rum Fabr.. larvas 

 sometimes on roses. Nematus ventrlcxsus Klg., larvae on gooseberries. Cimbex 

 frin a fata L. 



Fam. Uroceridae (Wood- wasps). Abdomen with first tergum split, and usually 



long, freely projecting oviposi- 

 tor (egg-borer). The females 

 bore holes in wood and deposit 

 // W//>/ x /\ their eggs therein. The larvae 

 bore further into the wood 

 and live a long time. Sin .r 

 L. 



FIG. 489. a, Larva of the bumble bee about to become 

 a pupa, b, Pseudo-pupa (Semi-pupa), c, pupa (after donaen 

 Packard). 



usually living in vegetable cells. 



Tribe 2. Grallicola. Ab- 

 stalked. Larvae 

 apodal and aproctous, 



Fam. Cynipidae (Gall-wasps). Thorax humped. Abdomen usually short, 

 laterally compressed. The ovipositor (egg-b6rer) arises on the ventral side, ami 

 is as a rule retracted. The females bore into plant tissues and cause, by the 

 irritation of an acrid fluid, an abnormal flow of vegetable thuds, thus giving 

 rise to the outgrowths known as ij fills, on which either one or several apodal 

 larvae feed. Certain galls, especially those of the oaks of Asia Minor (Alepjjo}, 

 contain tannic acid, and are on this account used in industry. In many species 

 the females only are at present known ; the eggs in such cases develop 

 parthenogenetically. Many larvas are parasitic in Diptera and AjMdes. 

 Cynips tjneronx folii L., Rltoditcs rost? L.. produces the bedeguar of roses. 

 xfitdcllaris Latr.. parasitic on the grubs of Su 



Tribe 3. Entomophaga. Abdomen stalked. Female with freely 

 projecting ovipositor (spine). Larvae apodal and without anus, 

 usually parasitic in the larvae of other insects. 



Fam. Pteromalidae. The larva? are parasitic in all possible insect larva?, 

 frequently in parasites, and pass through a complicated metamorphosis, ex- 

 tremely remarkable for the succession of very different stages. Pteromaltts 

 H L., Trlretx clar it-amis Latr., Plafi/yaxtrr Latr., (fig. 4.58). 



