NOTES FOR APRIL.
Itis very interesting in the spring to watch the gradual development of a frog from the egg, through the tadpole stage of its existence, till at last it assumes its final form.
The old frogs emerge from their winter hiding places in the mud, early in the spring, and during March their eggs may be found floating on almost every stagnant pond. A group of these eggs in their early stages of development looks like a mass of clear white jelly, containing numbers of black specks, each of which is really the germ of the future tadpole.
In order to watch the development, a group of the eggs should be taken and put in a shallow vessel of water, which, if kept in the house, should have a bell-glass, or some other covering over it, to keep out the dust.
The jelly-like mass which envelopes the future tadpole is so clear that all its changes can be easily watched. First the head appears, then a flat tail, and in course of time the nostrils, mouth, and large eyes, till at length the completed tadpole bursts open its gelatinous covering, and apparently not in the least embarrassed by its new surroundings, begins swimming briskly about, looking for something to eat. The time occupied in hatching varies in different countries, according to the climate, from four days to a month. In England the tadpole does not often appear till towards the end of April.
The following stages are even more interesting, especially for those who can take advantage of the transparency of the parts to watch the circulation of the blood through a microscope.
The body of the tadpole gradually gets broader, while the tail gets thinner and thinner, till it finally disappears altogether; but before that happens its place has been taken by two hind legs, which first appear under the skin and then gradually push their way through. The fore legs next appear, and so on through all the stages of development, till in a longer or shorter time, according to the amount of warmth, light, and food it can obtain, the complete frog appears.
But woe betide the unfortunate tadpole which, first of the shoal, attains to the dignity of possessing limbs, for so ferocious are the later ones, and so jealous of their precocious little brother, that they almost always fall upon him, and, not content with killing, never rest till every morsel of him is eaten. And unless several of the tadpoles assume their final change about the same time, this proceeding is repeated till their numbers are very considerably diminished, or, as sometimes happens, till only one survivor is left, who, having helped to eat all his brethren, instead of meeting with his deserts, is allowed to live on in peace, till some day in the course of his walks abroad, he, in his turn, is snapped up as a delicate morsel by some hungry snake or waterfowl.
Insects and flowers are much more closely connected with one another than we sometimes think.
Not only do many insects depend upon flowers for their food, but many flowers also depend upon the visits of insects to carry their pollen from one flower to another and so continue the life of their species.
There are some flowers, however, whose pollen is carried by the wind instead of by insects, and which are therefore an exception to this general rule. These, not needing to attract insects, are small and insignificant, with neither scent nor honey, but with a very large quantity of pollen. They generally flower early in spring, before the leaves are out, as these would catch the pollen as it is blown along by the wind, and prevent it reaching the flowers for which it is intended. Notice, for example, the flower of the oak, elm, ash, and Scotch fir.
April is a busy month in the garden. Auriculas and polyanthuses in bloom should be watered often, and shaded if the sun is very bright, and sheltered when the weather is cold; tulips also must be sheltered from severe cold, though they may safely be encouraged to grow now.
Seeds of perennials and biennials for flowering next year should be sown now, such as wallflowers, carnations, and pinks. Heartsease for autumn flowering should also be sown, and cuttings taken from old plants. Hardy annuals should be sown not later than the middle of April. Give them good soil, and do not cover the seeds too deeply with earth (some of the smallest kinds should only be sprinkled on the top), and when they begin to shoot up thin out the young plants vigorously; amateur gardeners almost always leave them too close together, but the more room they have the better and stronger they will grow.
If there is no greenhouse, or “heat,” half hardy annuals may be sown out in the open garden towards the end of April, and if diligently cared for they will grow well and thrive.
After a warm day, evergreens are benefited by syringing. Ivy that is wished to grow close should be clipped all over; and grass should be cut about once a week, and often rolled. It should not be allowed to get long before cutting the first time, or it will be troublesome to get into order again.
April is the month in which we welcome most of our spring bird visitors. The nightingale and cuckoo have already come and begun their song; the swallow and house-martin will arrive about the middle of the month, and are soon busy making new nests, or patching up old ones. The whitethroat appears towards the end of the month.
During the April showers the whole air seems full of song. Walking through woods ringing with bird music, we are once more reminded of the problem which so puzzled Daines Barrington. “Do the birds all sing in one key? And if not, why do the songs harmonise instead of producing unpleasant discords?” Perhaps it is the distance which lends enchantment and softens the discords. No doubt if all the songsters were in one room, the result would not be quite so happy.
Many eggs, larvæ and cocoons of butterflies and moths may be found this month among heaps of dry leaves, on low bushes, or trunks of trees. Grasses and rushes shelter several of the early species, which are already flying about, and some rare insects may be found now which cannot be obtained later in the season.