X. THE FROZEN POND.

The pond on the moor is frozen over. What an epoch in the history of all its inhabitants! For they are not mostly long-lived creatures, these pond-dwellers; a summer forms an appreciable part of their short existence. Theirs is but a precarious life at the best of times; they have always to steer close between the Scylla of drought and the Charybdis of freezing. Half their days are spent in enforced seclusion. In the summer the pond, which is their universe, is apt to dry up and fail them; in winter it stands its even chance of freezing solid and entombing them. To meet these two extreme contingencies, all the world of the pond has had to accommodate itself to the possible chances of its fickle environment. The newts, for example, come here to breed every spring. They must needs do so, indeed, because their young have gills like a salmon or a herring, and can only breathe in their earlier stages the diffuse oxygen held in suspension in water. Newts, in fact, start in life as fish, but develop, half-way through, into lizard-like animals with lungs and legs, because of the annual drying up of their native waters. All higher life, indeed, was originally aquatic; it is only just because ponds dry up in summer that the ancestors of beasts and birds and reptiles ever ventured on dry land, at first for a brief excursion, and afterwards for a permanence. We are all in the last resort the descendants of amphibians. There are two kinds of newt in this pond, each with its own peculiar plan for meeting the difficulty of winter quarters. The great crested newt, who is the most confirmed water-haunter of the two, retires to the mud at the bottom of the pond in late autumn, and there lies torpid as long as the frost lasts, returning to the surface to breathe when the weather improves again. But the smaller newt, a more adventurous soul, goes ashore in summer, when the pond dries up, and stops there for the winter, lurking in long grass at the bottoms of ditches, or hiding in caves and damp vaults or cellars.

There are no fish in the pond, of course, because it is not permanent; it dries up in August. But there are frogs and tadpoles by the thousand in due season; and, what is odder still, the frogs are there now, though you cannot see them. Indeed, frogs and newts are merely slight variations on the fishy type, evolved to meet this very want and to fill this very place in the economy of nature: practically speaking, they are fish which turn at last into terrestrial reptiles. During the earlier spring days, when the ponds are full, the parents lay their spawn among the sunk leaves of water-weeds; and soon the tadpoles emerge from their jelly-like eggs, and swarm at the edge in a seething black mass of bustling and jostling life. Then, as the pond gets low, and breathing becomes difficult, they proceed by degrees to drop their gills, and develop the rudimentary swim-bladder into a pair of true lungs. Soon four weak little legs with sprawling fingers bud out at their sides; and, hi, presto! they hop or crawl ashore as full-fledged air-breathers. At this point grave differences appear between them. The newts retain their tails through life, but the more advanced frogs drop or absorb theirs, and assume the shape of thorough-going land animals. In winter, however, the frogs return once more to the pond, and bury themselves in the oozy mud at the bottom, often huddled together in close-packed groups, for warmth and company. At first sight you might think they would be warmer on dry land; but this is not so, for they have little animal heat of their own, being cold-blooded creatures, and they would therefore get frozen whenever the surface temperature fell below freezing-point. But the pond seldom or never freezes solid; in other words, the degree of cold at the bottom never goes down to freezing; and so the frogs are comparatively safe in the mud of the bed. If you dig in the ooze in winter, you may turn up whole spadefuls of frogs and great crested newts in certain cosy corners, lying torpid and half dead, but waiting patiently for the returning sun of spring to warm them. So that even the frozen pond has a great deal more life in it than the casual townsman would at first imagine.

As for the snails and beetles, and other small fry of the pond, they mostly retire, like their enemies the frogs, to the depths for protection. The summer is their life; winter to them is merely a time to be dozed through and tided over. Many of the shorter-lived kinds, indeed, die out altogether at the first touch of autumn, leaving only their eggs or their pupæ to represent them through the cold season. In these cases, therefore, we might almost say that the species, not the individual, lies dormant through the winter. It ceases to exist altogether for the time, and is only vouched for by the eggs or spawn, so that each generation knows nothing by sight of the generation that preceded it.

But when spring comes round again, there is a sudden waking up into spasmodic activity on the part of the pond and all its inhabitants. The season has set in, and life is to the fore again. The greater newt, in imitation of the poet’s wanton lapwing, “gets himself another crest,” and adorns his breast with brilliant spots of crimson and orange. The mating proceeds apace; frogs pair and spawn; the water swarms once more with layer upon layer of wriggling black tadpoles. Now the great pond-snail floats at the top, and lays its oblong bunch of transparent eggs; now the water-crowfoot flowers; the diver beetles disport themselves amain; strange long-legged beasts that walk the water like insect Blondins, begin to stalk the surface on their living stilts; and dancing little “whirligigs,” who skim the pond, coquette and pirouette in interlacing circles. All nature is alive. Winter is forgotten; eating and drinking, marrying and giving in marriage, are the order of the day in pond and hedgerow. Then the crested newt proceeds to devour his smaller relative, and the tadpole to elbow his neighbour out of existence; and all goes merrily as wedding bells in the world of the pond—till winter comes again.