246 NORTH AMERICAN INSECTS. 
very slowly, and remain several years in the larva state, 
they often become injurious to whole forests of trees. When 
fully grown, they are about one inch long, when they make 
their cocoon; and in a few days after undergo their final 
transformation into the perfect insect. 
We now come to a much more wonderful, and, with one 
exception perhaps, the most interesting genus of the whole 
order Hymenoptera—a genus of world-wide notoriety, and 
one that seems to partake in a remarkable degree of that 
intelligence which naturally belongs to the highest order of 
animals. We mean 
The Ants (Formica). 
These insects are found in all parts of the globe, but in 
greater number and of larger size in the tropics, where 
their vitality is not affected by cold weather. ‘The genus 
Formica contains a great number of black, yellow, red, and 
brown species, of very different sizes, some being only two 
or three lines, while others are an inch long. Their head is 
broad, thorax small, and hind body large; their upper jaw 
is very wide, like a broad forceps; their antennz small, of 
a triangular or elbow shape, similar to those of the Snout- 
beetle; their eyes are very small, and the sting is some- 
times wanting. 
Each species live in a social community by themselves, 
in ant-hills, and is composed of males and females, who are 
provided with wings; and workers, who have no wings. The 
males and females, of which there is a great number, have 
nothing to do but to enjoy themselves and multiply their 
species. The wingless workers do all the necessary in-and- 
out-of-door business: they build their habitation, or ant- 
hill, of earth, pine-wood leaves, and woody fibres, with 
which they also manufacture their subterranean caverns: 
they feed the young ones, and carry the cocoons from one 
