338 INSECTS. HYMENOPTEUA. 



To this division belong the genera Spathius, Aphid'uts, Perilitus, Leiophron, Mi- 

 crodus, HormiuS) and Blacus of M. Nees d'Esenbeck. 



II. Maxillary palpi of six joints, the labial of four. 



Gen. SIGALPHUS, CHELONUS, AL\SIA, (mandibles tridentated) Lat. ; Ro- 

 GAS, CARDIOCHILUS, HELCON, KUBAZUS. Nees d'Esenbeck. 



The genus Anomalon of Jurine, according to Latreille, is composed of Ichneumo- 

 nides of which the second cubital cell, generally very small, is abortive. 



Gen. ICHNEUMON, Lat. 



Abdomen petiolate ; upper wings reticulated ; antennae compos- 

 ed of twenty joints and upwards, simple, setaceous, or fili- 

 form ; mandibles terminated by two teeth ; maxillary palpi 

 setaceous or filiform, long, of nine unequal joints, of which 

 the second is dilated, and the last three elongated and slen- 

 der ; the labial short, of four joints, the last ovate. 



I. necatorius, Lat. Black ; scutellum with two teeth, the posterior 

 border, that of the first ring of the abdomen, of the third and two 

 following, yellow ; the second ring with two points of the same 

 colour. Inhabits Europe. Lat. Nouv. Diet. xvi. 39. 



TRIBE III. GALLTCOL.E. (Diploleparice.) 

 Lower wings with at most one nerve ; the upper one radial cell, 

 two or three cubital, of which the first two, where there are 

 three, or the first only, where there are two, are complete ; 

 antennae of the same thickness, or thickening, without form- 

 ing a club, and of from thirteen to fifteen joints ; palpi short ; 

 ovipositor rolled up in a spiral form in the interior of the ab- 

 domen, and the extremity lodged in a groove of the belly. 



Gen. FIGITES, IBALIA, (Sagaris ;) CYNIPS, (Diplolepis, Geoffi) 



Gen. CINIPS, Lat. Geoff. Ichneumon, Lin.Chalcis, Cuv. 



No nerves in the lower wings ; antennae straight and filiform, 

 and generally of thirteen to fifteen joints ; palpi very short ; 

 ovipositor of the females lodged in a groove partly or entire- 

 ly ; upper wings with one radial triangular cell, and two or 

 three cubital ones, of which the third is very large ; body 

 short, arched. 



The insects of this genus are well known for producing the galls of commerce. 

 These productions are formed by the female inserting with her ovipositor the ova 

 in the leaves of plants, and the juices of the plant exuding by the opened ves- 

 sels form excrescences or tuberosities which are called galls ^ and in which the lar- 

 vae are found inclosed. The larvae finfl their food in the place in which they are 

 concealed, and they suck and gnaw the interior of the gall, which also increases in 

 size and solidity outwards in proportion as it is eaten within. Many of these galls, 

 considered generally, have one cavity, which incloses a certain number of larvas, liv- 

 ing in society ; others have many small cavities, between which there are communi- 

 cations ; in some there are more than a hundred cells, of which each is inhabited by 

 a single larva ; and in others are found only one cell, inhabited by a solitary indi- 

 vidual. The galls present many varieties in point of form ; generally, however, they 

 are rounded, and some have their name from their resemblance to certain kinds of 

 fruit, as nut-galls. One of the most common is extremely useful in the arts, enter- 

 ing into the composition of writing-ink. Among those of a rounded form, some are 



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