186 STREPSIPTER A . HOMOPTER A , 



to an extraordinary size in proportion to the rest of the animal. 

 The larvae appear to feed upon the fatty matter in the bodies of the 

 Bees and Wasps, on which they are found, without injuring their 

 vital parts ; and their production does not seem to cause the death 

 of the animals they infest. When full grown, their heads may 

 be seen projecting between the segments of the abdomen of the 

 Bee (Fig. 411, a). Here, too, they undergo their metamorphosis 

 into the pupa state ; remaining still inclosed in the larva-skin, 

 and bursting through both the larva and pupa cases, to make 

 their way forth as perfect insects. No distinct mouth has been 

 discovered in the larva, and its mode of obtaining nourishment 

 is unknown. Many points in the economy of these singular 

 insects are still uncertain; especially all that concerns their 

 reproduction. All the specimens yet discovered appear to be 

 males ; and it has not been yet ascertained when and how the 

 eggs are laid, or at what stage in the growth of the animals 

 infested by them, the parasites first make their appearance. 



ORDER YI. HOMOPTERA. 



715. THE Insects of this Order are distinguished from all 

 others which have, like them, the mouth adapted for suction, by 

 possessing two pairs of wings, usually composed of a firm mem- 

 brane, and not covered by scales ; and by having the anterior 

 pair, whatever may be their consistence, of the same substance 

 throughout, and roof-like when folded. They present many 

 curious anomalies both in structure and habit ; so that it is 

 difficult to assign any general character that shall include them 

 all. It is in the structure of the mouth that there is the greatest 

 agreement ; this is adapted for suction, the tongue being 

 elongated and channelled like a gutter, and being surrounded 

 by delicate lancet-like organs, with which the tissues of plants are 

 pierced. All the Insects of this group subsist on vegetable 

 juices; and some of them, from the amount of damage they 

 commit, are very injurious to the cultivator. Some of the 

 females are furnished with an ovipositor, provided with several 



