ANTS, BEES, WASPS, AND THEIR KINDRED 107 



drawing forward the wings of a newly dead bee, when 

 the fore- and hind- wing will be seen to move in unison. 

 A less obvious character of the Hymenoptera is the 

 partial or entire fusion of the first abdominal segment 

 with the thorax the " waist/' which is so marked a 

 feature in many families, coming not between the thorax 

 and the abdomen, but behind the first abdominal seg- 

 ment. Mandibles are always present in the capacity 

 of nipping organs ; but they are generally employed as 

 tools, and have comparatively little to do with the 

 direct service of the mouth. The maxillae vary greatly 

 in the different families. Among the saw-flies they are 

 not very unlike those of beetles and cockroaches ; but 

 in the higher families they are adapted for licking or 

 sucking. In the case of a hive-bee or a humble-bee, 

 for example, the parts are greatly modified and of 

 considerable length. When in close contact, they act 

 as a suctorial apparatus, or proboscis, which is often 

 spoken of as the insect's "tongue." But the real 

 tongue (hypopharynx) is only a part of the compound 

 organ, in which it occupies a central position. 



Hymenoptera undergo a complete metamorphosis, 

 the pupa being of the free type. It is usually, but not 

 always, enclosed in a silken cocoon spun by the full- 

 grown larva. The order is divided into two well- 

 marked sub-orders, of which the first 1 includes the 

 saw-flies and wood-wasps, or horn-tails, as the latter 

 are sometimes called. In all these insects the ab- 

 domen is more or less continuous with the thorax, 

 there being no marked constriction or " waist." The 

 ovipositor of the female is adapted for cutting or 

 boring, but never for stinging. The larvae are all 

 plant-feeders. Those which live openly upon the 

 1 Symphyta. 



