20 8 
TRANSFORMATIONS OF INSECTS. 
tubular hairs, which the ants are very fond of licking, and they 
thus appear to have some special secretion which pleases their 
hosts. It is a very remarkable fact that the larvae of these 
beetles cannot take their own nourishment, but they receive it 
from the mouths of the ants, and these extraordinary little 
beings thus have the instinct to nourish and to keep alive the 
beetle larvae, which afford them some pleasant luxury. 
There are some ants with arched mandibles, which are narrow 
and sharp, and which resemble warlike weapons rather than imple- 
ments of work. They belong to the genus Polyergus. The 
common species of this genus, Polyergus rufescens , is a small 
insect about a quarter of an inch long, and is a warrior, and does 
not care for building or any such trouble. It inhabits under- 
ground nests, where the brown and mining ants are found, but it 
does not make its own places of refuge, as it has no structures 
with which it can work, so it captures the workers of other colonies 
and employs them as slaves. Huber describes a curious scene 
in the life history of these ants, which he saw in the neighbour- 
hood of Geneva in 1804. He observed a great mass of ants 
which were red or russet in colour, and of tolerably large size, 
traversing a road. They marched in a body, and with great 
rapidity, and they took up a space of from eight to ten feet 
in length by three or four inches in breadth, and they 
passed over the road in a very few minutes, penetrated 
through a thick hedge, and moved on to a grass field, over 
which they marched in regular array, in spite of numerous 
obstacles which came in their way. They soon came near a nest 
of blackish coloured ants, which was situated about twenty paces 
from the hedge, the dome of it being higher than the grass. 
Several ants were round about the door of their nest, and im- 
mediately that they observed the approaching army they rushed 
upon the head of the column ; the alarm was given within, and a 
crowd came out from the underground works. The red ants 
quickened their pace, and soon pushed the black ones into their 
nest, they then clambered up the dome of the nest, many forcing 
themselves into the largest avenues, whilst others worked hard 
with their mandibles, so as to open a breach in the walls. This 
was soon done, and the rest of the invading army penetrated 
