The Girls Own Paper, Vol. VIII, No. 355, October 16, 1886 | Page 5

were eating, a movement which gave rise to the idea that they chewed the cud.
It is worthy of remark that other animals, which, though not rodents, need to possess chisel-edged incisor teeth, have a similar habit. Such is the hippopotamus, and such is the hyrax, the remarkable rock-haunting animal, which in the authorised translation of the Scriptures is called the "coney," and which in the Revised Version is allowed in the margin to retain its Hebrew name, "shaphan."
The enamel also has an important part to play in the structure of the molar teeth. Each tooth is surrounded with the enamel plate, which is so intricately folded that the tooth looks as if it were made of a series of enamel triangles, each enclosing the tooth matter.
This structure is common to all the members of the group to which the water-rat belongs. It is the more remarkable because we find a somewhat similar structure in the molar teeth of the elephants, which, like the rodents, have the incisor teeth largely developed and widely separated from the molars.
There is nothing in the appearance of the water-rat which gives any indication of its aquatic habits.
For example, we naturally expect to find that the feet of swimming animals are webbed. The water-loving capybara of South America, the largest existing rodent, has its hoof-like toes partially united by webs, so that its aquatic habits might easily be inferred even by those who were unacquainted with the animal. Even the otter, which propels itself through the water mostly by means of its long and powerful tail, has the feet furnished with webs. So has the aquatic Yapock opossum of Australia, while the feet of the duck-bill are even more boldly webbed than those of the bird from which it takes its popular name. The water-shrews (whom we shall presently meet) are furnished with a fringe of stiff hair round the toes which answers the same purpose as the web.
But the structure of the water-rat gives no indication of its habits, so that no one who was unacquainted with the animal would even suspect its swimming and diving powers. Watch it as long as you like, and I do not believe that you will see it eating anything of an animal nature.
I mention this fact because it is often held up to blame as a mischievous animal, especially deserving the wrath of anglers by devouring the eggs and young of fish.
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 animals to whom the soil had been hitherto left will fail to understand that they can no more consider themselves as the owners, and will in consequence do some damage to the crops.
Moreover, even putting their food aside, their habits often render them obnoxious to civilised man. The mole, for example, useful as it really is in a field, does very great harm in a garden or lawn, although it eats none of the produce.
The water-vole, however, is doubly injurious when the field or garden happens to be near the water-side. It is a mighty burrower, driving its tunnels to great distances. Sometimes it