THE INSECT WORLD. 



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There are also two kinds of winged forms, males and females, 

 both larger than the workers, and the females considerably larger 

 than the males. All the insects work their way down to the 

 lower levels or inmost galleries of the nest on the approach of 

 cold weather, and hibernate in the adult stage in a dormant con- 

 dition. In spring, with the approach of warm weather, activity 

 is resumed, and, usually some time during the early part of the 

 season, on a particularly bright, warm day, the newly developed 

 males and females leave their old home and swarm." By this 

 is meant that they leave the nest in which they were hatched and 

 fly about for a short time. They mate soon after, and are then 

 ready to start colonies of their own. None of them ever get 

 back to the old home, and if they do not succeed in founding a 

 *' hill," they perish in the course of a day or two. Exactly how 

 the different species start their colonies is not known, but in some 

 cases, certainly, the impregnated female strips off her wings and 

 starts a small nest in some convenient place, doing the best she 

 can under the circumstances, and laying only a few eggs. These 

 she brings to maturity, and they are usually of the small or 

 ''worker minor" type. When fully developed, these relieve 

 their parent from further mechanical work, increase the size of 

 the nest, and gather food as well as attend the young that are 

 still continually hatching. If circumstances favor, the nest grows 

 rapidly, and it may eventually become enormous in size, con- 

 taining millions of individuals, and ramifying for distances that 

 we have not yet succeeded in following to the end. The life cycle 

 of all the ants has not been definitely determined as yet, but 

 ' ' queens' ' have been kept as long as seven years and workers for 

 three or four. The food of ants is variable, — sometimes animal, 

 sometimes vegetable, and quite usually both. The same species 

 may feed upon fragments of insects and other animal matter, and 

 also upon plant tissue of various kinds. They are usually fond 

 of Hquid food, especially if it is sweet, and some species gather 

 ^ and store honey like the bees, although in quite a different man- 

 ner. In the more temperate parts of the United States ants 

 are only indirectly injurious, although they are never beneficial. 

 There is quite a common belief that ants destroy the plant-lice 

 among which they are frequently found ; but this is exactly con- 

 trary to the fact, for plant-lice play a very important and curious 



