英文科學(xué)讀本 第二冊·Lesson 13 Corn

Lesson 13 Corn

You know, Norah, when we were talking about starch, I made some to show you, said Fred. "I made it from some flour, and flour is made from wheat. Here are some grains of wheat. Do you know where they come from?"

They grew on plants in a corn field. said Norah.

Well, now, said Fred, "we are going to have a talk about these corn plants. Teacher told us we could understand the corn plants by looking at the stems of some tall grass. So Will and I have been hunting about to find some grass that would do. We have found some. Suppose we have a look at it.

We will begin with the leaves. They are long, narrow, and pointed, and not like most of the leaves we see. We call them blades of grass. If we hold them up to the light, we see that the veins run side by side, from one end of the leaf to the other. The veins are parallel. Look! There is a swelling or knot in the stem, where each leaf joins it. The leaves all spring from these knots or joints.

Now let us split open the stem with this knife. You see it is hollow.

But, said Norah, "I can't see what all this has to do with the corn plants."

Well, said Fred, "the corn plants are just like this grass. They are grasses. We call them the corn grasses.

Now we know, Fred went on, "that the grass and the corn plants both have tall hollow stems with joints in them, and long, narrow, pointed leaves. Each corn plant sends up five or six stems.

This grass, you see, has some small green flowers at the top of the stem. When the flowers die off, they leave the seeds behind in a long ear. The corn-grasses have green flowers too, and after the flowers, long ears full of seeds or grains. Here is an ear of wheat. If we pull the ear to pieces, we shall find a great many grains of corn. Each grain is held in a sort of shell of thin, light, but strong skin. This we call the husk. The husk protects the grain from the sun and rain, till it is fully grown and ripe."

SUMMARY

The corn that grows in the cornfields is a grass. It has a hollow, jointed stem, and long, narrow leaves. The corn grains grow in long ears at the top of the stem.