书城教材教辅科学读本(英文原版)(套装1-6册)
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第312章 第三册(137)

"The legs are always eight in number-four pairs. Insects, you know, have six legs. The legs are of great length, and each one consists of seven jointed parts. The spider, having no wings, has to rely on these long nimble legs in pursuing his prey."SUMMARY

The spider is not an insect. Its body is in two parts, and is not covered with overlapping segments. It has eight legs, and no wings. The eyes are single, and not in clusters. They are very prominent. On the front of the head are a pair of terrible claws. The spider is a ?erce, cruel, and sly hunter.

Lesson 48

The Vital Organs of the Plant

"Suppose we have another chat about plants to- night, Norah," said Fred. "Let us try again to think of some of our early lessons. We will begin with the root. Shall we?

"The root, you know, is that part of the plant which makes its way down into the soil. It has to hold the plant firmly in the ground, and supply it with earth-food from the soil.

"Some plants have fibrous roots. The fibers spring from the stem, and spread downwards through the soil. Grass and grain have fibrous roots, and so have all plants thatdie down ever y year. Such plants are called Annuals. We sow the seeds for them in the spring.