166 PR^DONES. SAND AND WOOD-WASPS. 



mate occupiers of the nest. In this habit, these insects closely 

 resemble the Cuckoo (351). In many points of structure, 

 the Chrysididee bear a strong resemblance to the Aculeate 

 Hymenoptera; and they may be considered as intermediate 

 between the two great divisions of the Order. 



692. Section III. ACULEATA PRJEDONES. The Hymenoptera 

 of the Aculeate division may be usually distinguished from the 

 Terebrantia, by the mode in which the abdomen is united to 

 the thorax. In the borers, it is in general closely jointed to 

 it, a structure which is evidently necessary for providing the 

 ovipositor with the requisite strength ; whilst in the stinging 

 Hymenoptera it is usually connected by means of a peduncle 

 or foot-stalk, which is often (as in the Wasp) extremely 

 slender, and of which the first appearance is seen in the Chry- 

 sididse, as just now mentioned. The Predaceous subdivision of 

 this group contains several families ; of which the most im- 

 portant only will be noticed in detail. 



693. The CRABRONID^E, LABRIDJE, BEMBECIDJE, SPHEGIDJB, 

 SCIOLIDJE, and MUTILID^E, may all be considered under one 

 general description ; they form a group, which may be termed, 

 from their peculiar habits, that of Fossores, or Diggers ; and 

 they are commonly known as Sand and Wood- Wasps. They are 

 solitary in their mode of life, and consequently no neuters exist 

 among them. In general the females excavate cells in the 

 ground, or in posts, timbers, &c. ; in which they deposit 

 together with their eggs various larvae or perfect insects, and 

 (in some species) even spiders, which are destined for the sup- 

 port of their progeny when hatched. Occasionally the insects 

 composing this store are first stung to death ; but sometimes 

 they are only slightly stung, and are finally killed by the larvae 

 when they come forth from their eggs, being in this manner 

 rendered powerless, whilst their bodies are prevented from 

 decomposing. The perfect insects are generally very active, 

 and fond of the nectar of flowers, especially those of the Umbelli- 

 ferous tribe. They delight in the hottest sunshine, flying and 

 running over sand banks exposed to the mid-day sun, and keep- 

 ing their wings in constant agitation; some of the tropical 



