Читать книгу Intelligence in Plants and Animals онлайн

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From all that has been written it must be evident that our first walking animal is by no means a poor or feeble creature. He has a chain armor woven into his leathery skin, with sharp, pointed spines, and snapping, beak-like claws to protect him; an excellent digestion and a capacious mouth to feed his greedy stomach, and a fine array of nerves, quick feeling and eyesight, and a wonderful apparatus for moving over the ground. When it is added to all these possessions the ability to close over the wound in the case of a lost ray and the growing of a new one, we see that his powers of living satisfactorily are by no means insignificant. But this curious walking apparatus of the Star-fish is far from being perfect in all his relations. They do not all walk by means of suckers any more than all sponge-animals build toilet sponge, or all slime-animals make chambered shells. Sure, the Rosy Feather-stars, for example, have no use for feet-tubes, as their lives are generally spent upon the rocks or nestled in bunches of sea-weed. Brittle-stars, as these are called, though closely related to the Star-fishes, are not easily confounded with them, for their arms are found to radiate from a clearly defined central disk, and there is no prolongation of their stomachs and ovaries into their interiors. The tube-feet pass out from the plates along the sides of the arms, instead of from the under surface as in the Star-fishes proper, and probably serve merely as a help for breathing, locomotion over the sands being effected by their long flexible arms. Their home is chiefly among the tangle and eel-grass, where their protecting covering affords them security from their many enemies.