THE SOCIAL INSECTS 



roofs of special underground chambers in the nests and are 

 almost incapable of movement. If they happen to fall from 

 their perch they are unable to get up again. They are fed by 

 other workers who also bring the liquid which distends 

 them. The repletes start life as ordinary workers, but before 

 their skeleton has fully hardened they are given so much liquid 

 food that their crop distends their abdomen and this condition 

 becomes permanent, lasting for months or even years. 

 Though the repletes form only a small proportion of the 

 workers, there may be two hundred or three hundred in the 

 nest. The repletes give up part of their store when solicited 

 by other workers, and it is presumed that they can thus keep 

 the whole colony going during a period of prolonged 

 drought. It is a matter of common observation that many ants 

 when returning from a visit to plant-lice have the abdomen 

 considerably distended, but normally it contracts again as 

 soon as they have shared out the food. This facultative 

 distension has been much exaggerated in the honey-pot ants 

 and has become permanent in the repletes. 



HARVESTING ANTS 



One group of food-gathering ants has been familiar from 

 remote antiquity, namely the harvesting ants. It was to them 

 that Solomon directed the attention of the sluggard. They 

 are found in many of the drier parts of the world, especially 

 round the Mediterranean basin. Many ants make some use 

 of seeds as a source of food and the British red ant, Myrmica, 

 already mentioned as a hunter and a collector of aphis excreta, 

 has also been observed bringing cornflower seeds into its 

 nest. Many seeds have a small part which contains more fat 

 than the rest, and this is especially eaten by ants. Some 

 botanists have, indeed, maintained that the fat-reserve of the 

 seed has been evolved to make it attractive to ants, just as 



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