seaside dwellers, such as prawns, are almost transparent in the water.
Others, like baby crabs, are green or 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?