382 THE INSECT WORLD. 
being mothers themselves, they share in the duties and joy of 
maternity. Alone, they decide on peace or war; alone, they take 
part in combats: head, heart, and arm of the republic, they ensure 
its prosperity, watch over its defence, found colonies, and in their 
works show themselves great and persevering artists.” 
The nests of ants (Figs. 361, 362) are known under the name 
of ant-hills. They vary very much, both as to their form and 
the materials employed in making them: wood and earth are the 
principal. That which strikes one at first sight, is the size of 
these dwellings, which form a curious contrast to the smallness of 
their builders. Each species of ant has an order of architecture 
peculiar to it. The Red Ant (Formica rufa), one of the com- 
monest in our woods, constructs a little rounded hillock with all 
kinds of objects—fragments of wood, bits of straw, dry leaves, the 
remains of insects, &c. This hillock, whose base is protected by 
material of greater solidity, is nothing more than the exterior 
envelope of the nest, which is carried underground to a very 
ereat depth. Avenues, cleverly contrived, lead from the summit 
to the interior. The openings vary in width; and, as night 
approaches, are carefully barricaded. They are opened every 
morning, except on rainy days, when the doors remain shut, and 
the inhabitants confined within. 
The ant-hill, or formicarium, is at first simply a hole hollowed . 
out in the soil, the entrance to which is masked by the building 
materials. But the miners do not cease to hollow out galleries 
and chambers, arranged by stories. The earth and rubbish are 
carried out, and serve to construct the upper edifice, which rises 
at the same time that the excavation grows deeper. It is a 
labyrinth bored in all directions. It contains corridors, landings, 
chambers, and spacious rooms, which communicate with each other 
by passages which are often vertical. All the corridors lead to 
a large central space, loftier than the others, and supported by 
pillars; it is here that the greater number of the ants congregate. 
These ant-hills often rise to a height of fifteen inches above the 
ground, and descend to an equal depth. The figure shows the 
interior of an ant-hill, drawn from nature. Outside it are to be 
seen some ants, occupied in sucking plant-lice. 
The group of Mason Ants contains a great number of varieties: 
