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 régime 
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 (Sphegide), which store paralyzed insects 
and spiders for their larve. The predatory régime 
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 digger-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 larve and as adults. The predatory régime 
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 
