INTRODUCTION OF INSECTS. 
107 
into wliicli their small dimensions enable them to retire, are 
all circumstances very favorable not only to the perpetuity of 
their species, but to their transportation to distant climates 
and their multiplication in their new homes. The teredo, so 
destructive to shipping, has been carried by the vessels whose 
wooden walls it mines to almost every part of the globe. The 
termite, or white ant, is said to have been brought to Rochefort 
by the commerce of that port a hundred years ago.* This 
creature is more injurious to wooden structures and imple¬ 
ments than any other known insect. It eats out almost the 
entire substance of the wood, leaving only thin partitions 
between the galleries it excavates in it; but as it never gnaws 
through the surface to the air, a stick of timber may be almost 
wholly consumed without showing any external sign of the 
damage it lias sustained. The termite is found also in other 
parts of France, and particularly at Rochelle, where, thus far, 
its ravages are confined to a single quarter of the city. A 
borer, of similar habits, is not uncommon in Italy, and you 
may see in that country, handsome chairs and other furniture 
which have been reduced by this insect to a framework of 
powder of post, covered, and apparently held together, by 
nothing but the varnish. 
The carnivorous, and often the herbivorous insects render 
an important service to man by consuming dead and decaying 
animal and vegetable matter, the decomposition of which 
would otherwise fill the air with effluvia noxious to health. 
Some of them, the grave-digger beetle, for instance, bury the 
small animals in which they lay their eggs, and thereby pre¬ 
vent the escape of the gases disengaged by putrefaction. The 
prodigious rapidity of development in insect life, the great 
numbers of the individuals in many species, and the voracity 
of most of them while in the larva state, justify the appella¬ 
tion of nature’s scavengers which has been bestowed upon 
them, and there is very little doubt that, in warm countries, 
* It does not appear to be quite settled whether the termites of France 
are indigenous or imported. See Quatkefages, Souvenirs d'un Naturaliste , 
ii, pp. 400, 542, 543. 
