118 ASSOCIATION OF ORGANISMS—THE WEB OF LIFE 
The most important and arduous duty of the workers is to 
look after the eggs, larvae, and pups, and these are distributed 
through the nest with due regard to variations of moisture and 
temperature, since both of these affect development. The queens 
are carefully tended, and their eggs are carried off to suitable 
chambers. From time to time these are carefully licked, and it 
is also said that they are smeared with nutritious fluid that is 
absorbed by the embryos. When the larve hatch out they are 
fed with great assiduity and their toilet requirements attended to. 
The full-grown larve spin cocoons, within which they become 
pupe (the so-called ‘ants’ eggs”), which also receive unremitting 
attention. The workers bite away the enclosing cocoons when 
the perfect insects are ready to come out. Some of them are 
workers, others winged males and females which fly about in 
swarms. After mating, the large majority of the swarming in- 
dividuals perish, but some of the females survive to found fresh 
communities, or sometimes to be taken into existing nests. 
The stings of Wood-Ants are not sufficiently well developed 
to be of use, but their poison-bags contain formic acid, which can 
be squirted to a considerable distance, and is an effective defence. 
This particular acid, as its name indicates (L. formzca, an ant), 
was first known as a product of insect-life. The strong mandibles 
of the workers are also weapons of no despicable character. These 
ants co-operate for offence and defence, and Lord Avebury (in 
Ants, Bees, and |Wasps) thus describes their tactics, and those of a 
related species:—‘formica rufa, the common Horse Ant, attacks 
in serried masses, seldom sending out detachments, while single 
ants scarcely ever make individual attacks. They rarely pursue 
a flying foe, but give no quarter, killing as many enemies as pos- 
sible, and never hesitating, with this object, to sacrifice themselves 
for the common good. Formica exsecta is a delicate, but very 
active, species. They also advance in serried masses, but in close 
quarters they bite right and left, dancing about to avoid being 
bitten themselves. When fighting with larger species they spring 
on to their backs, and then seize them by the neck or by an 
antenna. They also have the instinct of acting together, three 
or four seizing an enemy at once, and then pulling different 
ways, so that she on her part cannot get at any one of her 
foes. One of them then jumps on her back and cuts, or rather 
saws, off her head. In battles between this ant and the much 
