POISONOUS INSECTS AND THEIR RELATIVES 437 



The ants, bees, wasps, and their relatives that constitute 

 the order Hymenoptera, are the final insects to be con- 

 sidered among those irritating to man. 



The Hymenoptera is divided into two large subdivisions, 

 the boring Hymenoptera and the stinging Hymenoptera. 

 The members of the boring Hymenoptera have the end of 

 the abdomen furnished with an ovipositor in the form of a 

 boring organ with which holes or openings may be made in 

 the fruit, leaves, or stems of plants, or in the bodies of 

 other insects, in which the egg may be deposited. The 

 boring Hymenoptera, represented by the sawflies, horn- 

 tails, gall-flies, ichneumon-flies, and others do not generally 

 attack or seriously annoy man. It is said that species of 

 the genus Ophion occasionally sting human beings, causing 

 a transient but intense pain. 



It is among the stinging Hymenoptera that we find the 

 distinctly annoying forms, such as the bees and wasps. 

 The members of this subdivision have the abdomen 

 furnished with an ovipositor modified into a weapon of 

 defense, commonly known as the sting. It should be 

 understood that since the sting is a modified ovipositor, 

 only the females possess a sting. Male wasps, bees, 

 and hornets, do not, indeed cannot, sting. 



The sting of a worker (infertile female) honey-bee con- 

 sists of a straight, tapering, spear-like hollow organ com- 

 posed of three pieces surrounding a central canal. The 

 base of the sting is enlarged into a bulb-like portion which 

 is hollow and connects with the canal in the sting. There 

 are two sets of poison glands connected with the sting, 

 one of which contains a liquid substance having an acid 

 reaction and supposed to consist mainly of formic acid, 

 while the other gland contains an alkaline secretion, and 



