386 



ZOOLOGY 



system, to suffice for the larva till it pupates. Each species 

 always attacks a particular kind of insect and carries it home 

 as food for its larvae; thus Generis bupresficida always 

 attacks the larvae of the beetle Biiprestis, SpTiex flavipennis 

 attacks Qryllus, and S. albisecta various species of Oedipoda. 



Another allied family, the Chrysididae, often lay their eggs 

 in the nests of the Fossoria and other Hymenoptera. They 

 are green or black, and their sting is devoid of a poison-bag. 



Group 4. Apiaeiae (Bees). 



In the bees the body is thick and short, and as a rule 

 hairy. In the workers the tibia and tarsus, especially of the 

 posterior legs, are broadened and covered with hairs like a 

 brush ; these serve to gather and carry home the pollen 

 grains. The labium and maxillae are often very long, and can 

 reach to the nectaries at the base of some of the longest 

 flowers. Whilst obtaining food in this way bees very frequently 

 effect the cross fertilisation of the flowers they visit. The 

 anterior wings do not fold. Both the females and workers 

 have stings, which in many cases are provided with recurved 

 spines, so that if inserted into a foreign body they cannot be 

 retracted. 



The division of labour which plays such a prominent part 

 in the economy of the higher Hymenoptera reaches the highest 

 pitch amongst the bees. The queen-bee alone in Apis mellifica 

 — the honey bee — lays fertilised eggs, sometimes at the 



Worlcer-liee. Drone. 



FiQ. 221. — Apis mdlifica. 



Queen-bee. 



rate of 3000 a day; she and the workers live through the 

 winter, but the drones all perish in the autumn. The drones 

 are the males of the community ; they arise from unfertilised 



