英文科學(xué)讀本 第三冊(cè)·Lesson 03 Birds and their Covering

Lesson 03 Birds and their Covering

We have not had a chat about animals for a long time, said Fred. "Would you like us to start one this evening, Norah? We had a good lesson on birds today, and I think Will and I can tell you something about it."

Oh, said Norah, "I should like it very much."

Well then, you remember we talked about several animals last year, Fred began. "We had amongst others the cat, dog, sheep, pig, horse, cow, and rabbit. Now think of them, one by one. What sort of clothing have they?"

They all have different sorts of coverings, said Norah.

Quite true, said Fred. "But all birds are clothed with feathers."

Now I want you to think of something else. How do all those animals feed their young ones?

They nurse them, said Norah. "I have seen our Tabby nurse her kittens."

Did you ever see a bird nurse its young?

No, the parent birds feed their little ones with bits of food which they find for them. Birds do not nurse their young.

There is just one other point for us to notice now about birds, Fred continued. "All the animals we have mentioned live and move about either on the earth or under it. But what can you tell me about birds?"

Birds fly in the air, said Norah. "They have wings."

Quite right, said both boys. "Now, Norah, you know the three chief things about birds. Birds are the only creatures that are clothed in feathers. Birds do not nurse their young. Birds have wings and fly in the air."

But let us fix our attention now, said Fred once more, "on the covering of feathers. This is the warmest, lightest, and, at the same time, the most beautiful of all coverings."

Wait a minute while I go to the pigeon-house and get my little pouter. He is very tame, and will perch on my arm while we talk about his feathers.

Fred was back again in no time with his pigeon, and then he began. "Suppose we look first at the wings and tail. Notice these long feathers, as I spread out the wing. They have a stem, which we call the quill. These are the quill feathers. They are fixed into the skin of the bird by a sort of root. The bird makes use of these long feathers in the wings and tail for flying."

Now, if you run your finger over the birds body, you will find that the whole of the body is covered with smaller feathers, which form its real covering. These are the clothing feathers.

Notice that when I run my fingers over them the wrong way, I ruffle them up; but they can be easily smoothed back again into their proper position, and then they are seen to be beautifully arranged, one overlapping the other, so as to form a close-fitting coat.

Such a coat of feathers closely overlapping one another is of course very warm. But some birds, such as ducks and geese and swans, that spend much of their time in the water, both in winter and summer, are still further protected from cold. They have a close-fitting under-jacket of very small, fine, soft, fluffy feathers, which we call down.

Yes, said Norah, "I have seen the down on the geese at Christmas time, and how tiresome it is to pick it all off clean."

SUMMARY

Birds are clothed with feathers. They do not nurse their young. They have wings, and fly in the air. Birds have large quill feathers in the wings and tail, and clothing feathers to cover the body. Some birds have soft down under-jackets.