brown like the weed in which they
hide. Even the sharp eyes of the seagulls must be deceived by this
trick.

What a strange life they lead, these creatures of the shore! At times
they are deep under water, and they form part of the teeming life of the
ocean floor.

Then the tide falls and uncovers them. They are in the full light of day
again, the sun shines on them. Most of them cannot escape to the sea,
and so must face the enemies which prowl along the shore looking for
prey. So, from one tide to the next, the rock-pool is like a prison
containing prisoners of the strangest sort.

[Illustration: GULLS. 1. COMMON GULLS. 2. LESSER BLACK GULL. 3. GLAUCOUS
GULLS.]

EXERCISES

1. How is the sand formed?

2. Give the names of some of the animals to be found in the rock-pools.

3. Where do these animals hide?

4. Prawns and shore-crabs are not easily seen; why is this?

LESSON III.

BIRDS OF THE SHORE.

On some parts of our coast we find steep cliffs, with the sea beating
wildly at their feet. Elsewhere there is a sloping beach of sand and
shingle with, perhaps, dark rocks showing at low tide. We explored such
a beach as that in our last lesson. There are long, long stretches of
sand and thin grass in other places, or else mile after mile of muddy,
dreary, salt marshes.

Birds are to be found on every kind of coast. Some, like the Seagull,
wander far and wide. Others keep to the cliffs, and many find all they
need in the wide mud-flats. Such an army is there of these shore birds,
that we cannot even glance at them all in this lesson. So we will take a
few of them only--the Black-headed Gull, the Cormorant, the Ringed
Plover, the Oyster-catcher and the Redshank.

Out of all the many kinds of Gulls, you know the Black-headed one best.
If you live in London you can see and hear him, for he and his cousins
have swarmed along the Thames of late years. They find food there, and
kind people enjoy feeding the screaming birds as they wheel in graceful
flight over the bridges and Embankment.

The country boy, too, sees this Gull. He flies far inland, following the
plough, and he then rids the land of many a harmful grub. Because of
this habit, some people call him the Sea-crow. At all seaside places you
find him, and there he fights for his meals with the Herring Gull, the
Common Gull, the Kittiwake and others.

Really we should call this gull the Brown-headed, not the Black-headed,
Gull; for the hood