THE OCEAN WORLD. 



such he considered the architectural product of the polyps. In other 

 words, Beaumur introduced into Science the views which he had keenly 

 contested with their author. But from that time the animal nature 

 of the coralline has never been doubted. 



Without pausing to note the various authors who have given their 

 attention to this fine natural production, we shall at once direct our 

 attention to the organization of the animalcules, and the construction 

 of the coral. 



M. Lacaze-Duthiers, professor at the -Jardin des Plantes of Paris, 

 published in 1864 a remarkable monograph, entitled "L'Histoire 

 Naturelle du Corail." This learned naturalist was charged by the 

 French Government, in 1860, with a mission having for its object the 

 study of the coral from the natural history point of view. His 

 observations upon the zoophytes are numerous and precise, and worthy 

 of the successor of Peyssonnel ; but for close observation, practical 

 conclusions, and popular exposition, the world is more indebted to 

 Charles Darwin than to any other naturalist. 



A branch of living coral, if we may use the term, is an aggregation 

 of animals derived from a first being by budding. They are united 

 among themselves by a common tissue, each seeming to enjoy a life of 

 its own, though participating in a common object. The branch seems 

 to originate in an egg, which produces a young 

 animal, which attaches itself soon after its birth, 

 as already described. From this is derived the 

 new beings which, by their united labours, pro- 

 duce the branch of coral or polypidom. 



This branch is composed of two distinct parts : 

 the one central, of a hard, brittle, and stony nature, 

 the well-known coral of commerce ; the other 

 altogether external, like the bark of a tree, soft 

 and fleshy, and easily impressed with the nail. 

 This is essentially the bed of the living colony. 

 The first is called the polypidom, the second is 

 the colony of polyps. . This bed (Fig. 47) is 

 much contracted when the water is withdrawn 

 from the colony. It is covered with salient 

 mammals or protuberances, much wrinkled and furrowed. 



Each protuberance encloses a polyp, and presents on its summit 



Fig. 47. Living Bed of Coral 

 after the entrance of the 

 Polyps. 



(Lacaze-Duthiers.) 



