As is often the case in the life-history of animals as well as of men,
the blame is laid on the wrong shoulders. If the destruction of fish be
a crime, there are many criminals, the worst and most persistent of
which are the fish themselves, which not only eat the eggs and young of
other fish, but, Saturn-like, have not the least scruple in devouring
their own offspring.

Scarcely less destructive in its own insidious way is the common
house-rat, which eats everything which according to our ideas is edible,
and a good many which we might think incapable of affording sustenance
even to a rat. In the summer time it often abandons for a time the
house, the farm, the barn, and seeks for a change of diet by the brook.
These water-haunting creatures are naturally mistaken for the
vegetable-feeding water-vole, and so the latter has to bear the blame of
their misdoings.

There are lesser inhabitants of the brook which are injurious both to
the eggs and young of fish. Among them are several of the larger
water-beetles, some of which are so large and powerful that, when placed
in an aquarium with golden carp, they have made havoc among the fish,
always attacking them from below. Although they cannot kill and devour
the fish at once, they inflict such serious injuries that the creature
is sure to die shortly.

I do not mean to assert that the water-vole is never injurious to man.
Civilisation disturbs for a time the balance of Nature, and when man
ploughs or digs the ground which had previously been untouched by plough
or spade, and sows the seeds of herbs and cereals in land which has
previously produced nothing but wild plants, he must expect that the