ARTHROPODA 1 19 



may add (if we except the silkworm), the most useful, of 

 insects. They have a large head, with compound eyes 

 and three ocelli, mouth fitted both for biting and lapping, 

 legs formed for locomotion as well as support, and four 

 wings equally transparent, and interlocking by small 

 hooks during flight. The females are usually provided 

 with a sting, or borer. The larvae are footless, helpless 

 grubs, and generally nurtured in cells, or nests. Such 

 are the honey bees (Apis], humble bees (Bombus\ 

 wasps ( Vespa\ ants {Formica), ichneumon flies, and gall 

 flies. Those living in" societies exhibit three castes : 

 females, or " queens " ; males, or " drones " ; and neu- 

 ters, or sexless " workers." There is but one queen in a 



a 



FIG. 79. Honey bee (Apis mellifica) : a, female; b, worker; c, male. 



hive, and she is treated with the greatest distinction, even 

 when dead. She dwells in a large, pear-shaped cell, 

 opening downward. She lays three kinds of eggs : from 

 the first come forth workers, the second produces males, 

 and the last females. The drones, of which there are 

 about eight hundred in an ordinary hive, are marked by 

 their great size, their large eyes meeting on the top of 

 the head, and by being stingless. The workers, which 

 number twenty to one drone, are small and active, and 

 provided with stings, and hollow pits on the thighs, 

 called " baskets," in which they carry pollen. Their 

 honey is nectar elaborated in the crop by an unknown 

 process ; while the wax is secreted from the sides of the 

 abdomen and mixed with saliva. There is a subdivision 



