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Overview

Birth of a Coral Island

Nature of Coral

Flowers of the Reef

The Echinoderms

Amazing Defensive Weapon

Turtles of the Reef

Strange Behavior of Reef Crabs

A Deadly Killer

World's Largest Shellfish

Strange Oysters of the Reef

Rare fish of the Coral Seas

Unusual Vegetation

Birds in Millions

Angling Unsurpassed

       

 

flowers of the reef

The nearest relatives of the corals are the sea anemones, many of which resemble the chrysanthemums or cactus dahlias of our gardens. They have been referred to as the "flowers of the Reef."

In most other regions, sea anemones rarely grow beyond a few inches in diameter, but on the Barrier Reef they may be seen as large as dinner plates.

Sea anemones are usually found in the form of disks covered with tentacles and attached to rocks by means of a cylindrical "stalk." Although seemingly delicate and innocuous, they possess myriads of poison darts that are shot out from the tentacles when they are touched; and it is by this means that

the anemone obtains its food. If a small fish or a shrimp happens to brush against these tentacles, the great battery of "machine guns" opens fire, and the victim is immediately paralysed. Then the tentacles gather round it and pass it from one to the other towards the centrally situated mouth which opens wide to receive it. When digestion in the stomach is complete, the remains of the victim are passed back through the mouth, and the tentacles convey them to the edge of the disk where they are finally discarded.

Anemone Fish. Although the darts of most of the anemones of the Reef cannot penetrate the human skin, there are some species, known as "stinging anemones," which possess darts of such power that they can cause an intense irritation resembling the stinging of a nettle. But here is a remarkable fact. Certain small fish, known as anemone fish, brilliantly ornamented with vertical, scarlet bands, are completely immune from the anemone's stings. It is their constant habit to move lazily about the anemone's tentacles, to hide amongst its folds, or even to invade the anemone's stomach in search of food which the anemone has been at such great pains to collect. This association is an extremely intimate one, and if the anemone is removed the fish acts as if it has lost its home. There is a shrimp, also, with the same habits.

How is it that these fish and shrimps are unaffected by the anemone's stings when other animals, similar in all respects as far as we know, so quickly succumb to them? No satisfactory explanation for this most extraordinary immunity has as yet been advanced.

 

 

 

 

   
Wonder Book of Knowledge