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also placed another set of curious little creatures, called the animalcules; not because the animalcules are like plants, but because they are so unlike any other kinds of animal, that he did not know where else to place them. This lowest great division, called the Radiated, contains the feeblest kind of animals which our Creator has seen it good to place on this globe of land and water.
When I first studied the strange tales belonging to the history of these lowest creatures, I was greatly amused and delighted. I was astonished to find that many of them are so much like plants, that it is often difficult to believe they are animals. Indeed it is only within the last few years that naturalists have decided that some of them are actually living creatures; for the fact that they all required air and food did not of itself settle the question whether or not they were animals.
Only observe the air and food which a tree requires to keep it alive. Its roots suck up the juices which they find in the earth; and by some wonderful power which the great Creator has put in a tree, these juices are made to run up the stem. They run up partly under the bark, but mostly through the cells or holes in the fresh wood that was made during the former year; and these juices run up the stem, something in the way that water runs up the sides of a piece of loaf sugar: only in the tree these juices do not stop, but on they go till they reach the leaves. Now every leaf is full of innumerable little holes, through which air and water rush in and mix with the drawn-up juices; and as every leaf is made up of a top skin and of an under skin, with fine fibres running between them, the fresh sap runs first along the top part of the leaf, and then passes to the under side of the leaf. During this passage through the leaf, the air changes the quality of the pumped-up juices. Sometimes the air prepares the sap to become sweet, sometimes sour or bitter; sometimes it prepares it to turn to a clear gum, sometimes to a
thick juice like tar, just according to the laws the wise Creator has seen it good to establish. As soon as the air has made this change, the sap flows back into the tree, and going down under the bark, it forms a band of new wood, and likewise nourishes the woody fibre of the great trunk.
Animals have no roots by which to gather up the nourishment they require: their food is received by a mouth, and passes down into a cavity called the stomach, where it is melted or dissolved. The juices drawn out of the received food, are then carried all over the animal by innumerable little tubes, called arteries and veins. Yet air must always mix with these juices, or the animal will die. Some creatures draw the air into their blood through little holes in their sides,-flies do this; others draw the air in by gills—such as fishes; others draw air down into the chest by breathing. In the chest the air meets with the new juices, and turns them to a bright red. This bright red blood keeps the bodies of all back-boned animals warm, and makes
So far we have seen that both vegetables and animals want two things—they want food and air. What then is the difference between a plant and an animal? The great difference is, that vegetables always absorb, or take up their food by the roots or outside of their bodies, whilst animals always absorb, or take up the juices of their food from cavities in the inside of their bodies. And these two modes of support make an important difference in vegetable and animal life. Vegetables become fastened down to one place, that their roots may absorb the moisture around them; whilst animals, carrying their food with them, are generally left at liberty to move about. Then again, vegetables have no feeling and no wills; whilst animals feel pain, and not only move about from place to place, but have strong wills.
All the higher orders of animals have two sides to
their bodies, and these two sides match one another,
just as the one half of our faces matches the other half; but plants have no two sides alike; they grow round and round a centre. Their flowers grow in the same way. Look at a daisy; it has a middle, and all its petals, or ornamental parts, grow round that middle.
In thit round way the lowest of all the animals grow;
for we shall find that the creatures, which are scarcely superior to vegetables in their powers, are formed with a middle like a daisy. In this middle is their mouth, and round this
middle stand the few organs, by which, at their own good will, they take in their food. Therefore naturalists have agreed to call these kinds of animals by two names. One name is Zoophyte, which is a Greek word, meaning animal and plant. The other name is Radiated, or rayed. These radiated or zoophyte animals mostly live under water, and seldom move from the place where they first settle down.
Arachnida-spider tribe; named from
Arachne, a woman celebrated for her skill in spinning, and who was fabled to have been changed into a spider.
The spider belongs to the class called Arachnida, which consists of animals enclosed in horny rings, and which breathe by holes in their sides.
In order to find him, we must peep into dusty holes and corners in stables, barns, and houses :—we must ramble in the garden, and search amongst shrubs; we must look into rolled-up leaves, -into the cups of flowers,-into holes in stones, and holes in the ground:
we must examine brick walls ;- we must look carefully, and step lightly over the dewy grass and the fresh stubble field. And if we wish to do more, we must mount a high church steeple, and lifting up our eyes, we shall perchance see spiders sailing in the air still higher above us.
Do you think our hunt for spiders would then be over? No, indeed! If we went to some of the fen ditches, we might happen to find a large spider, floating on the water in a boat of its own making. And if we looked far down into the clear water of some other ponds and ditches, we might perhaps see a spider all alive, comfortably nestled
in a bright silvery house of her own preparing. There she sits, fearing no evil; for just as her Maker has taught her, so she has filled her little house with air, and fastened it down by silken cords to the quiet green leaves at the bottom of the pond.
If we notice the habits of these spiders, we shall find that some can run, some can leap, and some can fly on streamers of silk of their own spinning; that some lay snares, and others hide in ambush. We shall find that they follow different employments; that some are weavers, some are tent-makers, some are masons, and some are carpenters; that some are hunters, some jumpers, some swimmers, and some wanderers.
During the winter, spiders are sleepy and dull; but for the greater part of the year they are busily employed in catching their food, and in tenderly caring for and Tearing their young. In all they do, spiders show great activity, energy, perseverance, and industry; and display so much skill, that they may truly be said to be most wonderful little creatures.
A spider is an articulated animal, because around its soft body are many horny rings or hoops : which rings in some parts are joined together by à tough skin to form joints, and in other parts they are pressed so closely to one another, that they make a firm case.
The rings of crabs and lobsters are formed of hard
lime or chalk, but the rings of a spider are softer, being made of more horny materials. And when horn is thin, it possesses the valuable property of elasticity, or slightly yielding with a spring. Spiders have no gills; some species have two, and others eight holes in their sides, through which they breathe. These holes open into little tubes that take the air down into sacs or bags in the body. The inside of these tubes is lined with a skin that folds over in plaits, and these plaits are full of little veins that take in the air, and mix it with the blood.
Did you ever remark, as a spider ran past you, that its body was divided into two parts ? The front part is called the thorax. The thorax is the hardest portion of the body; and all the principal organs of the spider, such as its head and legs, are fastened to it. The other part of the spider's body is soft, and only covered with a thick skin; this is called the abdomen. The abdomen contains the stomach, the air sacs, and the bags of gummy silk, from which the spider makes its threads. These front and hinder parts are joined together by a slender tube.
The male has generally four pairs of legs; the female five pairs, one pair more being given to her, that she may carry her silken bag of eggs, and yet be able to do as much work as the male spider.
The legs of spiders are rather long.
You know how fine a spider's leg Male Spider. looks; and yet this fine leg is jointed, and has several strong muscles or little cords running down each of its sides. These muscles give the spider power to move quickly, and to hold tightly; and they also enable it to lift its body up from the ground, and to keep it steady upon its many-jointed legs.
The worm has no legs; crabs and lobsters scrape their stout limbs slowly along, and lay them close to the ground;