SOCIAL LIFE OF WASPS 27 



that of the bee-hive and the wasps' "bike." In 

 the social evolution of these Hymenoptera there 

 have evidently been two divergent lines one 

 towards honey-storing and the other towards 

 predatory alimentation. The honey-storing regime 

 has its climax in hive-bees, with many gradations 

 leading up to that pitch of perfection; and down 

 at the base of this line it seems that we must, for 

 anatomical reasons, include the solitary digger 

 wasps (Sphegidae), which store paralyzed insects 

 and spiders for their larvae. The predatory regime 

 has its climax in some of tropical social wasps, 

 while many others, not less predatory, called 

 Eumenids and Pompilids, remain at the solitary 

 level. And just as the predatory djgger-wasps 

 or Sphex-wasps, mentioned a moment ago, seem 

 to go with the bees, so there is a family of " honey- 

 wasps " (Masarids) which go with the main body 

 of the wasps, though they do not practise the 

 paralyzing device, and are, indeed, vegetarian, both, 

 as larvae and as adults. The predatory regime 

 appears to be the more primitive of the two, and 

 it has been suggested that honey-storing was re- 

 sorted to by types whose poison was not suited 

 for the preservation of animal food. In any case, 

 the broad fact is that social organizations have 

 been evolved on the hive-bee line of storing honey 

 and on the social-wasp line of supplies of fresh 

 meat. There has been an interesting dichotomy of 

 vegetarians and carnivores! 



According to Dr. Roubaud, the first chapter in 



