THE SOCIAL INSECTS 



small enclosed chamber, but is an elaborate, instinctive 

 performance. 



At this time, also, the queen begins to lay eggs. Some of 

 these are eaten and probably help to provide food for the 

 fungus. Others hatch and others again may provide food for 

 the youngest grubs. Soon after the first workers hatch, the 

 colony begins to collect vegetable fragments or to cut leaves. 



TYPES OF NEST 



Ants' nests are in many respects simpler than those of bees 

 or wasps, and this may give the colonies an advantageous 

 flexibility. Even so, there is a considerable variety in the 

 types of nests, some of which are remarkable structures. The 

 commonest type is built in the ground, either under a log or 

 stone or with a mound raised over it; more rarely there is 

 almost no external sign. The mounds are built by the ants, 

 bringing up the earth a few grains at a time, especially in 

 the early summer. Such mounds in England are often con- 

 fused with mole-hills, but they are made of much finer earth 

 and the ants can be found by digging into them. By tunnell- 

 ing in all directions, and leaving pillars to support the roof, 

 they are able to make as convenient a nest as a bee or wasp, 

 but in a much simpler way and with less work. 



The larger mounds certainly take a long time to build, 

 and many of them must be twenty years old or more. Since 

 queen ants have been kept in captivity for more than fifteen 

 years, and since replacement of the queen is possible as in the 

 honey-bee, the colony can live for long periods without 

 difficulty. According to whether it is dry or wet, hot or cold, 

 the workers shift the brood about to different parts of the 

 mound, to give them the right conditions. Some ants are 

 said to have two nests, one for the summer and another, in a 

 more protected situation, for the winter. 



i34 



