Quite lazily it floated about in the water, now under a stretch of seaweed, all purple and opalescent like ropes of wonderful colors, now through the clear, bright current past the gaping mouth of a shark. But the shark, although always on the watch for something to devour, did not get the little polyp, and soon it came to a submerged rock deep under the waves. This seemed a very good resting place, and there the polyp stayed.
Days passed, weeks lengthened into months, and still the polyp kept to its place on the under-sea rock. But it was not drowsing and sleeping like a lazy creature. It was busily at work, for the very minute it landed on the rock it decided to make a house.
Now you must not think that it could not work, because, although it did look like a drop of jelly and was small and curious, it was alive. It had arms, very, very tiny arms, finer than the finest silk thread in your mother’s workbasket, and so thin and delicate looking that nobody could see them. But those arms were stronger than they looked, and with them it held on to the rock tight and fast.
Then, what a queer house-making! The little, jellylike body began to swell. It raised itself up in the shape of a tube, and around the edge of the tube came a little rim. This rim was the beginning of the house of the polyp.
The waves rolled on. The sun beat down brightly and hotly as it always beats down in the South Sea country, and then came another change. A knot rose in the middle of the jelly, and out of that knot reached a mouth and feelers.
Now the work began in earnest. The polyp began to eat, to eat as greedily as a boy who has had not a bit for a whole day. It took in chalk and phosphorus from the sea food that came its way, yet it seemed never to get enough, and all the while the little feelers kept reaching out for more food and pouring it into the open mouth. As it ate, the chalk it took in piled around the little rim, which I told you was the beginning of the house, and although the polyp wanted much to hold some of that nice chalk food in its mouth long enough to get the full taste, it could not. The white substance went right down and piled up on the rim; so it is no wonder that the little creature was always hungry.