WASPS, SOCIAL AND SOLITARY 



almost absurdly heavy sense of responsibility for future 

 generations transforms the hitherto happy-go-lucky fe- 

 males into grown-up wasps with serious views on market- 

 ing and infant foods. Each one makes a separate nest 

 and provisions it by her own labor ; and in many cases a 

 new nest is made for each egg. There is no cooperation 

 among them ; although in certain genera, as Aphilan- 

 thops and Bembex, a number of individuals build close 

 together, forming a colony. The nests may be made of 

 mud, and attached for shelter under leaves, rocks, or 

 eaves of buildings, or may be burrows hollowed out in 

 the ground, in trees or in the stems of plants. The adult 

 wasp lives upon fruit or nectar, but the young grub or 

 larva must have animal food ; and here the parent wasp 

 shows a rigid conservatism, each species providing the 

 sort of food that has been approved by its family for 

 generations, one taking flies, another bugs, and another 

 beetles, caterpillars, grasshoppers, crickets, locusts, 

 spiders, cockroaches, aphides, or other creatures, as the 

 case may be. 



When the egg- lay ing time arrives the female secures 

 her prey, which she either kills or paralyzes, places it in 

 the nest, lays the egg upon it, and then, in most cases, 

 closes the hole and takes no further interest in it, going on 

 to make new nests from day to day. In some genera the 

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