Within the Deep | Page 4

looks up instead of down. Its mouth gets a queer one-sided look, owing
to the twisting of the bones in the head.
Many people think that the dark upper part of a flat fish is the back, and
the white under part is the stomach. We have seen, however, that this is
not so, for flat fish lie on one side.
For the rest of its life the Plaice will remain flat, with two eyes looking
up, and a twisted head. But its colour alters. The side on which it lies is
white; the upper side becomes brown and speckled, dotted over with
red marks. This is a good disguise. Its enemies cannot distinguish the
Plaice from the pebbles and sand around it. They might swim over it,
and yet not see the thin, flat, brownish body pressed down on the bed of

the sea.
Also, these flat fish have a wonderful way of changing colour. Put them
on light sand, and they become lightish. Put them on dark sand and
pebbles, and they soon match it by becoming brown and mottled. This
is a most useful dodge where so many enemies abound, all swifter in
the water than the slow-swimming flat fish.
If you look for flat fish in an aquarium, you will not easily see them.
Now and again one will swim up, with a wavy motion of its body. On
settling again, it shuffles and flaps about, works itself into the sand,
hiding its edges well under, and then, hey presto! it is gone! If the flat
fish are so hard to find in a tank, you may be sure it would be
impossible to find them on the sea bed. They are poor swimmers, but
perfect hiders.
As far as we can tell, they feed on other living creatures. The ocean
floor is a huge dining table for them, where they find very mixed
dinners. They eat small fish, sand-worms, shell-fish, Shrimps and
young Crabs. The Plaice has strong, blunt teeth in its throat, and is well
able to grind up the shells of Cockles and other molluscs, swallowing
the juicy contents.
Now we have seen that the Plaice is first a floating egg, and then a tiny
transparent "round" fish. It sinks to the sea bed, lies on one side, and
becomes a flat fish like its parents.
These little baby flat fish, not much larger than your thumb-nail, crowd
in the shallow, sandy parts of the sea near the coast. There they often
end their lives in the shrimp-trawl, as we have already noticed.
After leaving this "infants' school" the Plaice, and other small flat fish,
go to deeper water. There they feed and grow fat. Our fishermen know
where to find them. Indeed, these special fishing grounds are so well
known that flat fish are scarcer than they used to be. Some kinds are
much too dear ever to be seen on the poor man's table.
There is a special net for catching flat fish, called a trawl. This is a

large net, dragged over the bed of the sea by ropes, or steel wire,
attached to the sailing vessel or steam trawler. The net is kept open
under water by means of beams or boards.
When the flat fish are disturbed, they rise a foot or two from the sea
floor, and are then swept into the gaping mouth of the deadly trawl.
Once in, there is no escape. There they remain, pressed together, until
the net is hauled up and emptied.
EXERCISES
1. Give the names of five kinds of flat fish. 2. How does the Plaice
escape its enemies in the sea? 3. What is the food of the Plaice? 4. How
are flat fish usually caught for the market?

LESSON III
SEALS
There are many different kinds of Seal; the family is a large one, but all
have one thing in common--the fish-like body, with toes joined
together by a web. Anyone who has seen the diving power of a Seal,
and its wonderful way in the water, will agree that the "flippers" of the
Seal are as useful as the fins of the fish.
In fact, the flipper beats the fin, for the Seal earns his dinner by chasing
and catching fish. He slips through the water with perfect ease, and
seizes the darting fish in their own home. The Seal is nearly always
hungry, but so wonderfully quick that his hunting is made easy for him.
It is quite another matter on land, where his best pace is a waddle and a
shuffle; but his life is in the wide sea, where he can feed and sleep as
easily as other mammals can on land.
Seals are easily tamed, and soon become fond of their owners. Some
fishermen