SEA MAT.
We see, then, that (1) green sea-weed grows by the shore; (2) brownish-green sea-weed likes deeper water; (3) red sea-weed grows in deep water; and (4) in very deep water there is no weed at all.
We must not forget the grass of the sea. It grows in narrow blades, often a yard in length, and as wide as your thumb. It is not a sea-weed, but a real flowering plant, which, for some reason or other, loves to grow under water. It creeps in the sand and mud, with green leaves growing up as thick as corn in a cornfield.
All these waving green leaves make large meadows in the sea; and sea-snails, fishes, and crabs hide in it, just as all manner of living things hide in the grass of our meadows. The proper name of this strange plant is Sea Wrack. When dried, it is useful for packing up china, and covering flasks of oil.
Now we come to the real use of sea plants. They are food for all the hosts of small animals of the sea. These eat it as it grows; or else, like the mussel and oyster, swallow the tiny scraps of it which float everywhere like so much dust.
The shell-fish, and other animals which feed on sea plants, are themselves eaten by other sea creatures, and these in their turn are eaten by crabs, lobsters and fish, which are eaten by us. It reminds you of a chain. The first link in the chain is the sea plant, the last links are the fish and ourselves. So, you see, the weeds and grass of the ocean are of very great value indeed.
EXERCISES
1. Give the names of three common Sea-weeds.
2. What is the colour of the weed found in deep water?
3. Why cannot Sea-weed grow in very deep water?
4. In what way are sea plants most useful?