ic shock, and then eats them.
The electric power comes from the body of the Ray; if it wishes it can
send a deadly shock through any fish which ventures near. Without chance
of escape, it is at once stunned, and falls helpless.

We come now to some formidable dangers of the deep--big strong fish, so
well armed that they roam the seas without fear. On page 52 you see a
picture (No. 2) of the Saw-fish, one of the Shark family. It is a large
fish, and carries a big saw on its head, with which it stabs sideways at
its prey.

Imagine, if you can, a Shark about fifteen feet long and weighing a ton
or so. Now suppose the top jaw of this monster to be drawn out into a
hard, flat blade six feet in length. Then suppose there are sharp ivory
teeth, one inch apart, fixed on each side the blade, and you have an
idea of the Saw-fish. This strange Shark is said to be as strong as it
is fierce. It kills its prey by tearing them open with side blows from
its sharp, two-edged saw. Its big mouth is fitted with a great many rows
of needle-like teeth.

The Sword-fish wears a different weapon--a lance instead of a saw. He is
not a Shark, but a cousin of the beautiful Mackerel. This warrior of the
deep is more dreaded than the Saw-fish, and braver than any Shark. His
speed in the water is marvellous; it makes him safe from attack. He
carries in front of him a terrible weapon, and all sea-creatures hasten
from his path as fast as they can.

You may have seen the Sword-fish in a museum. There is a fine one in the
London Natural History Museum, where there is also a "sword" from one of
these fish, driven eighteen inches into the solid oak of a ship. The
Sword-fish never thinks twice about attacking, no matter if his enemy is
ten or twenty times as large as himself. He sees a Whale, and, like a
flash, hurls himself at it, stabbing his sword as deep as it will go
into the Whale's side. With a twist of his body the sword is wrenched
free, only to be driven savagely in again.

EXERCISES

1. Mention three ways in which sea-creatures try to escape their
enemies. 2. How do the Sting-fish and Sting Ray defend themselves? 3.
What is the Saw-fish like? 4. How does the Sword-fish attack its prey?

LESSON IX

THE FISH OF OUR ROCK-POOLS

The pools left by the falling tide have many an interesting thing to
show us. There are living creatures in plenty, besides the pretty weeds,
shells, and other objects. Shrimps, Prawns and Crabs abound in th