270 NATURAL HISTOET. 



have a peculiar prolongation of the last segment, which 

 in one division of the order is an ovipositor, and in the 

 other is a sting. The Hymenoptera are farther distin- 

 guished by a remarkable development of the instinctive 

 faculties, especially those which have a complicated so- 

 cial organization of their communities, as the Bees. 



461. The metamorphosis in this order is complete, the 

 pupae being quite inactive, and the larvse are more im- 

 perfect than in any other order. In most of the species 

 ihey have no feet, and resemble worms. The larvae of 

 some of them, however, are like caterpillars, and have 

 eighteen or even twenty feet. Jaeger says of them that 

 they live " in clean places, such as cells artificially built 

 of wax, pieces of wood, leaves, or mortar ; or they dwell 

 in wood, in holes under ground, in gall-apples, or oak- 

 balls, and many live in caterpillars ; but none inhabit car- 

 rion, dunghills, or other putrid and filthy places." 



462. None of the Hymenoptera are very large, and 

 some are exceedingly small. In numbers this order is 

 inferior only to the Coleoptera, and it has been estimated 

 to contain one fourth of the whole insect world. Though 

 the Hymenoptera are the most numerous and largest in 

 tropical countries, they are widely distributed in almost 

 every part of the earth. They are mostly great workers, 

 and none are nocturnal, but all do their work in the day. 

 Some of them are very useful to man, the Bees supplying 

 him with honey and wax, and the Gall-insects with a 

 material valuable for making ink, and especially for 

 coloring. 



463. We divide the order into two groups: 1. The 

 Terebrantia, or Borers, whose females have ovipositors ; 

 2. The Aculeata, or Stingers, in which the females have 

 a sting, or piercer, connected with a reservoir of poison. 

 I will notice but a few families in each group. 



464. The family of Gall-flies is one of the most prom- 

 inent among those of the first group. These insects, 

 with their ovipositors, make slits in various parts of 



