英文科學(xué)讀本 第三冊(cè)·Lesson 39 The Fish and its Food

Lesson 39 The Fish and its Food

Isn't there something else you would like to learn about the fishes, Norah? asked Fred.

Well, said his sister, "I've been looking at the fishes in your picture book, and I find that they all have small, sharp, pointed teeth in both jaws. There are a great many of them, but they don't seem to be meant either for tearing or chewing. I should like to know what food the fish feeds upon, and how it feeds."

Then suppose we have a closer look at the teeth, said Fred. "The teeth are, as you say, simply little sharp spikes, but they all point backwards towards the throat. Where have we seen teeth like this before?"

The snakes have teeth just like this, said Norah. "They feed upon animals, and swallow their prey whole."

Fishes, said Fred, "feed on one another, and they too swallow their prey whole without waiting to chew it. They are very fierce and greedy, and from the largest to the smallest, prey upon and devour each other. They hunt their prey through the water as the lion, tiger, and other fierce flesh-eaters hunt theirs on the land."

This explains, said Willie, "why they are made for easy and rapid movement through the water. At one time they are the hunters, at another they are the hunted prey."

The backward pointed teeth are meant to seize the prey, said Fred. "They must be strong enough also to hold the struggling, slippery victim fast, while the work of swallowing goes on."

There is just one other thought, Norah, Fred continued. "All fishes come from eggs. Next time you get a herring, open it and take out the roe. If it is a hard roe, you will see that it consists of an immense number of little grains or balls. Each of these is a tiny egg, and would have become a fish."

I daresay you are thinking, 'What an immense number of eggs from one single fish!' So it is, but let me tell you that these eggs, after the spawning, are the favorite food of many water animals.

Even the young fishes that come from the spawn of one kind feed on the eggs laid by others. Then, too, these same young fry, as the little baby fishes are called, form the chief food of all others that are large enough to prey upon them.

SUMMARY

The fish has small, sharp teeth, pointing backward, but no cutting, or grinding teeth. They devour other fish, and swallow their prey whole. Fishes lay eggs in immense numbers. The roe of the fish contains the eggs. The young fry that come from these eggs form the food of other fishes.