342 THE WORLD OF ANIMAL LIFE 



The drones are not idle, like the drone bees, but take their 

 share in the work of the nest, and make themselves very useful 

 in clearing out the galleries. It is their duty, also, to remove 

 the body of any wasp or grub that may chance to die. The 

 drones, however, do not make their appearance until late in the 

 summer. 



We get an idea of how hard a wasp has to work when we 

 learn that a large nest will contain nearly sixteen thousand cells, 

 the inhabitants of which have to be fed several times a day. And 

 wasps have not learned the art of storing up food, like the bees, 

 but are obliged to depend entirely upon what they can contrive to 

 pick up from day to day. 



The cells, too, are used several times, an egg being laid in each 

 almost directly its tenant has left it. An important part of a 

 wasp's duty, therefore, is to thoroughly clean out each cell as soon 

 as it is empty, in order that the queen when she comes round 

 may find it quite ready to receive her and her egg. 



As soon as the chilly days of autumn arrive, all the grubs are 

 taken out from the cells, carried to a little distance, and put to 

 death. This seems a very cruel proceeding ; but it is not actually 

 so. For, if the grubs were left in their cells, they would slowly 

 starve to death for want of the food which the workers could no 

 longer procure for them. 



Before this slaughter takes place, however, there is great excite- 

 ment in the nest, for hundreds of queens and drones have been 

 born, and these fly away to seek their fortunes. The drones die 

 in a short time; but the queens, hiding under loose bark, in hollow 

 trees, or in moss, live through the winter and form nests of their 

 own in the following summer. As for the workers, the first frosty 

 night kills them. 



ICHNEUMON FLIES (Family ICHNEUMONID^) 



While watching a caterpillar nibbling we may sometimes see 

 a little black fly perch upon its back. She reminds one, as she sits 

 upon the caterpillar, of a starling sitting on the back of a sheep. 



