446 INSECTA. 



membranous, either widened at its extremity, or long and filiform, 

 having the pharynx at its anterior base, and being frequently covered 

 by a sort of sub-labrum or epipharynx. They have four palpi, two 

 maxillary and two labial. The thorax consists of three united seg- 

 ments, of which the anterior is very short and the two last are con- 

 founded in one. The wings are laid horizontally on the body. The 

 abdomen is most commonly suspended by a little thread or pedicle 

 to the posterior extremity of the thorax. The tarsi consist of five 

 entire joints, none of them being divided. The ovipositor and sting 

 are generally composed of three long and slender pieces, two of 

 which serve as a sheath to the third in those which are provided 

 with an ovipositor, and one alone, the superior, has a groove under- 

 neath for lodging the two others. In those where this ovipositor is 

 transformed into a sting, this offensive weapon and the oviduct are 

 serrated at the extremity. 



The Hymenoptera undergo a complete metamorphosis. Most 

 of their larvae resemble worms and are destitute of feet; such, for 

 instance, are those of our second and following families. Those of 

 the first have six hooked feet, and frequently from twelve to sixteen 

 others that are simply membranous. These latter have been named 

 pseudo-caterpillars. Both kinds have a squamous head provided 

 with mandibles, maxillae, and a lip; at the extremity of the latter is 

 a fusus for the transmission of the silky material that is to be em- 

 ployed in constructing the cocoon of the nymph. 



Some feed on vegetable substances, while others, always destitute 

 of feet, devour the carcases of Insects, together with their larvae, 

 nymphs, and even eggs. 



To remedy their want of locomotive powers, the mother furnishes 

 them with provisions, sometimes by transporting aliment into the 

 nests she has prepared for them, which are frequently constructed 

 with so much art as to excite our wonder and surprise, and some- 

 times by depositing her eggs in the body of the larvae and nymphs 

 of Insects, on which her progeny are to feed. 



Other larvae of Hymenoptera, also destitute of feet, require more 

 elaborated and frequently renewed supplies of aliment, both vegeta- 

 ble and animal. These are reared in common by neuters forming 

 communities, of which they have the sole care; their labours and 

 mode of life will always continue to excite our admiration and as- 

 tonishment. 



