Children who are fond of country walks, and who use their eyes well,

喜欢在乡村漫步并且善于观察的孩子们

will be sure to notice in early spring little lumps of jelly floating on some pond by the roadside.

一定在早春时分看到过这样的场景：路边的池塘中经常会漂浮着一小块一小块的胶状物体。

This jelly-like stuff consists of a number of frogs' eggs or "spawn. "

这些胶状物质由大量的青蛙卵, 叫做“卵块”组成。

If we look at the spawn very closely, we shall see a great many black specks.

仔细观察, 就会发现这中间有很多黑色斑点,

Each of these specks is the centre of an egg.

每一个斑点就是青蛙卵的核心部分。

Let us return to the pond a month later.

一个月之后再回到池塘,

The spawn has gone, for all the eggs have burst open, and out of each one has come a little animal called a tadpole.

这些卵已经不见了, 因为它们全部破裂开来, 从中钻出了一种名叫蝌蚪的小动物。

Tadpoles are very funny-looking little things about an inch in length, each with a large round black head and a flat tail.

蝌蚪的样子非常有趣：体长一英寸左右, 脑袋又大又圆, 尾巴却是侧偏的。

They swim about in the water by the help of their tail, and they are very much like little fishes in many other ways.

它们通过摆动尾巴在水中游走, 除此之外, 它们和鱼还有很多类似之处。

They have little pink gills, which stick out on each side of their head.

蝌蚪脑袋的两侧分别长有一个粉红色的小鳃。

By its gills the tadpole can breathe the air which is dissolved in the water, just as a fish does.

通过这个器官, 蝌蚪便能够像鱼那样呼吸溶于水中的空气。

The little creature soon dies if it is taken out of the water, for it cannot breathe the air as we do.

它们离开了水, 很快就会死去, 因为它们无法和人类一样呼吸空气。

Each tadpole has a mouth with tiny teeth to gnaw the plants on which it feeds.

每只蝌蚪的嘴巴里都长有细小的牙齿, 用来刮食植物。

It is very curious to watch the changes that take place in the tadpole during the three months or so that it lives in the water.

蝌蚪在水中生活三个月的时间, 这期间, 它们的身体能够发生很多有趣的变化。

The gills become covered over, and lungs grow inside the body to do their work.

鳃逐渐被覆盖起来, 身体内部长出了肺, 用于进行呼吸。

The tail becomes shorter, and near it two legs break through the skin.

蝌蚪的尾巴变得更短, 而旁边则长出两条小腿。

Then other two legs come out nearer to the head.

很快, 头部附近也会出现这样的两条腿。

The tadpole is now able to walk, and to breathe the air just as we do, so it crawls out of the pond and lives in the damp grass.

现在, 蝌蚪能够爬行了, 而且可以像人类一样进行呼吸。因此, 它们会离开池塘, 进入到潮湿的草地中生活。

Its tail becomes still shorter, and soon disappears.

它的尾巴会变得更短, 然后便消失不见了。

Now it is no more a tadpole; it has become a young frog.

这时, 它不再是蝌蚪, 而是发育成为幼年青蛙。

Every one must have seen frogs jumping about in the wet grass by the roadside on a summer evening.

大家肯定都在夏季傍晚时候的路边湿草地里, 看到过一蹦一跳的青蛙。

They are quite harmless, and you may take one in your hand without any fear.

它们不会对我们造成任何威胁, 因此你不必害怕, 可以拿起来放在手中仔细观察。

But if you do pick one up to look at it, be very careful not to hurt it.

然而, 如果你真的这样做, 请不要弄伤它。

Look at the squat, stumpy body of the animal, with its very short neck and three-cornered head.

你可以看到它矮胖、粗短的身体, 短短的脖子以及三角形的脑袋。

The frog is about two or three inches in length, and is mottled with brown and yellow on the back; but it is lighter in colour underneath.

青蛙的体长大约在两到三英寸, 背部长满了棕黄色的斑点；但是它的腹部颜色却比较明亮。

The skin has no fur or hair, but it is covered with a slimy fluid.

青蛙的皮肤上没有任何毛发, 但是却覆盖着一层黏滑的液体。

The two hind legs are long and Strong. Each of the hind feet has five toes, which are joined by a web.

青蛙的两条后腿又长又壮, 每只后脚都有五根脚趾, 通过蹼连接在一起。

The two front legs are much shorter and weaker.

两条前腿较短, 也远没有那么粗壮。

The front feet have only four toes each, and they are not webbed.

前脚只有四根脚趾而且没有蹼。

The limbs of the frog remind us of those of the rabbit;

青蛙的四肢与兔子颇为相似,

for with both these animals it is the hind legs which do most of the work in helping them to move about.

因为这两种动物都主要依靠后腿进行运动。

The frog has no tail; and although it has a backbone, it has no ribs.

青蛙没有尾巴；虽然长有脊柱但是却没有肋骨。

Its two eyes are large, and stand far out from its head.

青蛙的两只眼睛很大而且突出在脑袋之外。

Each eye has two eyelids, the under eyelid being made of thin and clear skin.

每只眼睛都长有两层眼皮, 下面那层眼皮由轻薄的透明皮肤构成。

The frog has a large mouth; but as it does not chew its food, it has only a few tiny teeth in its upper jaw.

青蛙的嘴巴很大；但是, 它很少会咀嚼食物, 因此只有在上腭处长有几颗小牙齿。

The tongue of the frog is most useful to the creature in catching the flies and other small insects on which it feeds.

青蛙的舌头非常有用, 就是依靠它来捕食苍蝇与其他小型昆虫。

It is joined to the lower jaw in front, and not at the back as our tongues are.

舌头与下腭的前端相连, 而我们的舌头则是长在下腭的后端。

Thus the tongue of the frog lies in the mouth pointing backwards.

因此, 青蛙的舌头蜷缩在嘴巴里, 朝向后方。

At its tip there is a kind of sticky pad.

它的舌头顶端有一片沾满粘液的区域。

When the frog sees a fly which it wants to catch, it thrusts out its tongue till the sticky pad touches the insect, which is then drawn into the frog's mouth.

当青蛙看到一只想要捕捉的苍蝇时就会伸出舌头, 当那块粘液区域接触到猎物时后者便成为了青蛙口中的美食。

The red tongue is thrust out and pulled back so quickly that you can hardly see it move.

红色的舌头瞬间吐出并收回, 你几乎看不到它的移动情况。

Have you ever noticed that the frog is always swallowing something?

你有没有注意到这样一个现象：青蛙总是在吞食东西?

What he swallows is air; and this is the only way in which the air gets to his lungs.

它吞食的就是空气, 正是通过这样一种方法, 青蛙的肺部才能吸收到空气。

Frogs breathe very slowly, and do not take into their bodies so much air in proportion to their size as we do.

青蛙的呼吸非常缓慢, 由于体型相差甚多, 它所需要的空气远没有人类那么多。

For this reason the frog's blood is cold, while our blood is warm.

因此, 青蛙属于冷血动物, 而人类则是恒温动物。

Frogs do not eat plants, so they do no harm in a garden.

青蛙不以植物为食, 不会破坏我们的花园。

But they do a great deal of good in such a place; for they feed on insects and slugs, and other small animals which do eat plants.

实际上, 它们还是花园的卫士, 因为那些以植物为食的昆虫与鼻涕虫正是它们的猎物。

Frogs are most often seen in damp and wet weather, for then they come out of their hiding-places to enjoy the moisture.

青蛙最喜欢潮湿的天气, 那时, 它们都会从藏身之处跑出来。

They like water because it helps to keep their skin moist.

它们喜欢水, 因为这样可以保持皮肤湿润。

If their skin gets dry, they soon die.

如果皮肤变得干燥, 那么青蛙很快就会死亡。

Never hurt the poor frogs, for they do no harm but much good.

千万不要伤害可怜的青蛙, 因为它们对人类有百利而无一害。

When you hear them calling "Croak, croak, " to each other in the ponds, do not throw stones at them.

当你听到它们在池塘中用“呱呱”的叫声与同伴交流时, 请不要往水中扔石头。