Within the Deep | Page 7

find. You can look at him, yet not see him! For he takes the same colour as the rocks and sands of his home. Amid the glinting lights and shadows of his rock-pool, with a background of sand, rock, and weed, this little fish is nearly invisible. Of course it is a dodge, and a useful one, to escape the eye of the enemy!
Perhaps you will not think the Spotted Goby so clever at nest-building as the Stickleback. He likes to use a "ready-made" house, whereas the Stickleback finds his own "bricks and mortar." In the pools of the shore there is no lack of houses to let, the empty homes of shell-fish are there in plenty. So the little Goby, when nesting time comes, hunts round for the empty shell of a Cockle lying with its hollow side to the sand.
This shell is to be used as the roof for the nursery. The Goby's next task is to make a hole beneath the shell. He sets to work and, by scooping out the sand, makes a hole about as large as a marble. To keep the sand from tumbling in, he smears the hole with slime, which soon binds hard like mortar. Now the nursery is nearly ready; but a passage-way is made, passing under the edge of the shell, and then, to make things quite safe, the whole roof is covered with sand: it then looks more like a bump in the sand than a fish-nursery.
The female Goby enters the nest, and leaves her eggs in it; and then the little father fish is left in charge. He rests on the sand, near the entrance. When the little ones appear, he seems to think he has done his duty. So away, he swims, not staying, like the father Stickleback, to guard the youngsters. Again we see that the father, and not the mother, is the builder and nurse.
[Illustration: CORALS OF MANY KINDS.]
That very strange creature, the Pipe-fish, has the most peculiar nursery of all. He uses no building material! No made-up nest of weed or sand for him! No, he prefers to carry his eggs in his pocket. To be more exact, there is a small pouch under his body, and there the eggs are kept until they hatch. Meanwhile, the Pipe-fish goes about his affairs in the pool as if nothing particular had happened. You will see more about this funny little fish when we come to our lesson on "The Fish of our Rock-pools."
EXERCISES
1. What are the eggs of the Skate and the Dog-fish like? 2. How does the Sea-stickleback build his nest? 3. Where would you find the Sand Goby, the Pipe-fish, and the Sea-stickleback? 4. How does the Sand Goby build its nest?

LESSON V
THE OGRE OF THE DEEP
The ogre of the fairy-tale is bad enough, but, for evil looks, the Octopus is worse still. With his tough, brownish skin, knobbed like the toad's back, his large staring eyes, his parrot's beak, and ugly bag of a body, the Octopus is a horrid-looking creature. Add to this eight long arms twisting and writhing like snakes, and you have an idea of the most hideous inhabitant of the deep.
Then, like the ogre, the Octopus lives in a cave, and goes forth at night to claim his victims. He tears them to pieces, and returns to his dark cavern when daylight comes.
Before seeing how this ugly monster lives, eats, breathes and fights, we must know something of the way he is made. In the first place, it may surprise you to know that the Octopus's body is made on the same plan as that of the snail. The ogre of the ocean and the Garden Snail are second cousins! Their family name--mollusc--means soft-bodied.
But there are such numbers of molluscs that we split them up into different orders, just as a big school is split into classes. The Octopus belongs to an order of molluscs with a long name, which only means head-footed. Why is he called head-footed? The snail, as you know, has one broad foot under its body. The foot of the Octopus is divided into eight strips. These long strips are set round his head, hence the name head-footed. Because there are eight of these long feet he is named octo-pus or eight-feet.
The feet--or arms, or tentacles, as they are called--are joined at their base by a skin. It makes a sort of webbing. In the centre of this is a horny beak, usually of a brownish colour. It is just like a parrot's beak, only of thinner and lighter stuff. There are two parts to it, the top one curving down over the lower one. Behind this beaked mouth is a hard, rasping tongue. On each side of the head is a big, staring