412 ZOOLOGY. 



regions of the globe. Finally, these abdominal appendages 

 have at other times a more complex structure, and form an 

 offensive weapon, as in bees and wasps, or an apparatus 

 destined to secure a depot for the eggs of the insect in a 

 place adapted for the development of the young. The sting 

 of the wasp and bee is formed of two sharp stylets, lodged in 

 a horny stalk or sheath, having each a furrow, along which 

 flows the poison secreted in a small gland situated close to it. 

 In the state of repose, the whole apparatus is drawn within 

 the body of the animal ; but when the insect wishes to use 

 it, the sheath is protruded, and along with the sting is driven 

 into the skin of its enemy. Sometimes it is imposible to 

 withdraw it, and the whole sting separates then from the 

 body, remaining implanted in the wound, causing the speedy 

 death of the insect. The male is always stingless, and thus 

 can be handled without danger ; but the female and the 



Fig. 431. The Foenus ; Ichneumon or Cuckoo Fly. 



working bee are provided with it, and its sting produces a 

 very painful inflammation. The auger of the fcenus (Fig. 431), 

 of the ichneumons, and of many other insects, has a somewhat 

 analogous arrangement ; and we remark also, in general, a 

 serrated edge, by which the ichneumon divides the entrails, 

 of the animal or the tissue of the vegetable in which it pur- 

 poses depositing its eggs. It is by piercing in this manner 

 an oak of the Levant that a small insect called cynips gives 

 rise to the formation of the gall-nut, of which so much use 



