TRACHEATA 381 
As a rule, the males are smaller than the females. They 
live in communities, which comprise, besides the winged males 
and females, a number of wingless workers or neuters, These 
Fia, 214.—Formica rufa (Wood-ant). 
1. Female. 2. Male. 3. Neuter. 
are in reality aborted females, and, like the functional indi- 
viduals of that sex, are provided with poison glands. The 
poison consists of formic acid, and is ejected into wounds made 
either by the sting or the biting mandibles. Some of the 
workers, as is the case in the Termites, are specialised as 
“soldiers” with very formidable jaws and large heads. These 
defend the ant-hills when they are attacked. 
The workers or neuters survive the whole year, hibernating 
during the winter months. Some of the females also may 
hibernate, but the greater number of both males and females 
live for a short time only, during the summer. No food is 
stored up in the ant nest or formicarium for winter consump- 
tion, as those individuals which persist through the cold 
weather become torpid and cease to feed. With the return of 
spring the females which have persisted lay eggs, and these, or 
in some species the eggs and larvae of the preceding autumn 
which have lasted through the winter, develope into a new 
brood, producing males, females, and workers, The larvae are 
most carefully tended by the workers, which feed them with 
semi-digested food from their own stomachs. The sexes pair 
whilst flying in the air; the males then die, the females cast 
their wings and either start off to form a new colony or are 
led back by the workers to the old. The ova are very small. 
The structures which are commonly called the eges of the 
ants are the white oval cocoons. 
The nests are usually excavated in the ground or in a 
