Corals, Worms, etc. 



some transformation from the calcium chloride or calcium 

 sulphate of the sea-water. Sluggish creatures they are, 

 living in calcareous castles of indolence ! In silence they 

 spread and crowd and smother one another in a struggle 

 for standing-room. The dead forms, partly dissolved and 

 cemented, become a broad and solid base for higher and 

 higher growth. At a certain height the action of the 

 breakers begins, great severed masses are piled up or roll 

 down the sloping sides. Clear daylight at last is reached, 

 the mound rises above the water. 



" The foundations are broadened as vigorously out- 

 growing masses succumb to the brunt of the waves and 

 tumble downwards. Within the surface-circle weathering 

 makes a soil, and birds resting there with weary wings, or 

 perhaps dying, leave many seeds of plants the beginnings 

 of another life. The waves cast up dormant life which 

 has floated from afar, and a terrestrial fauna and flora 

 begin. It is a strange and beautiful story, dead shells of 

 the tenderest beauty on the rugged shoulders of the 

 volcano; the slowly laid foundation of the reef-building 

 polyps ; at last plants and trees, the hum of insects and 

 the song of birds over the coral island." 



Turning for a moment to the common starfish, we are 

 confronted with an undoubted case of animal ingenuity, as 

 exhibited by the creature's manner of feeding. The star- 

 fish, though muscular, is a soft-bodied creature, and his food 

 consists of bivalves, mussels and the like. Now the star- 

 fish has no means of piercing the shell of its victim as does 

 the whelk, or of causing it to rot away as do certain 

 sponges ; it relies on main force to accomplish its object. 

 The common starfish is a five-rayed creature, and at the 

 centre of the rays on the under surface its mouth is 

 situated. When a suitable mussel is found, the first care 

 of the starfish is to place its victim below its mouth, with 

 the help of the innumerable little structures, called tube 

 feet, with which the under surfaces of its rays are studded. 

 Having placed its prey into position, the starfish raises 



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