S76 



msECTA— ORDER HYMENOPTERA. 



Fig. 65.— Gall-Flt 



(Cynips kolldri, Hart.). 



Slightly magniiietL 



few nervures visible on the fore-wings forming one large cell near the centre. 

 The abdomen is short, slightly compressed, and much elevated. A common 



British species is figured. It is hardly necessary to remind 



Gall-Flies our readers that the principal ingredient in ink is obtained 



(Oallicoloi). from the galls of a Levantine species of Gynips. Some of our 



own galls are not unlike a cherry, or 

 other fruit ; and there are foreign galls which are much 

 larger and more tempting in appearance ; some of these 

 are called " Apples of Sodom." 



Many of the gall-flies appear at different seasons of 

 the year in two different forms, one in which the sexes 

 are separate, while the other consists exclusively of 

 females, or rather of individuals capable of self-repro- 

 duction. Sometimes one form is winged, and the 

 other apterous and subterranean. It is needless to 

 say that until their habits were discovered, the two 

 broods were regarded as belonging not only to different 

 species, bub to distinct genera. Another noteworthy circumstance relative 

 to galls is their extreme liability to attacks of parasites. You may collect a 



very large quantity of some kinds of galls, and breed hmi- 

 Gall-Parasites. dreds of specimens of different species of insects from them, 



and yet never obtain a specimen of the original gall-maker; all 

 will be parasites, and not a few will be a small parasitic species of Gynipida. 

 The Entomophaga, or truly parasitic groups of Hymenoptera, include the 

 families Chalcididce; Proctotrypidce, Braconidce, Ichneumonidce and Evaniicke. 



The female usually pierces the body of the caterpillars, or 



other victims whiolr she attacks, with her ovipositor, and 



lodges an egg in each wound. In other cases, the eggs are 



deposited on the eggs or larvae of their victims. Eggs thus 



attacked never hatch ; but ichneumoned larvse generally 

 attain their full growth, and then die, when the larvae of the parasite, which 

 have been feeding on it all the time, often emerge from it, and form 

 their own cocoons round the dead body of the caterpillar. In other cases, 

 the larva assumes the pupa-state, and the parasites pupate within it, emerg- 

 ing from the pupa-skin instead of the butterfly. 



The Ghalcididm are a very extensive family, divided into many sub-families. 

 The antennae are generally 13-jointed, consisting of a long basal joint and a 



series of short ones. The females 



are generally provided with a long 



or short ovipositor, which, in the 



genus Leucospis (Fabr.), is curved 

 These are among the largest 



family, and though not British, 



are found in Southern Europe, 

 black, wit4i yellow markings, and re- 



Parasitic 

 Hymenoptera 



{Entomophaga). 



Family 



Chalcididce. 



over the back, 

 species of the 

 several species 

 They are 



semble small wasps, but may at once be distin- 

 guished from them by the very rudimentary and 

 incomplete neuration of the wings. Leiicnspis and 

 several other genera among the larger Glialcididce 

 have very thick hind femora, toothed on the under-surface. , . 



The genus GalUmome (Spin.), to which many species which are parasitic m 

 galls, belong, are considerably smaller, rarely measuring more than about 



Fig. 66. 

 grandis. 



