180 FUNCTIONS AND INSTINCTS. 



that keep gradually diminishing the mass of 

 waters, but also islands, which emerging from 

 the ocean, in process of time are covered with 

 vegetation, and fitted to receive and maintain an 

 animal population with man at their head. The 

 species principally engaged in this great work is 

 the coral, called by Linne the muricated Madre- 

 pore, 1 and generally known by the name of white 

 coral; but Lamarck seems not to have been satis- 

 fied as to this species, since it is excluded from 

 his list of madrepores, though he refers to four, 

 if not five, varieties of it as distinct species. Its 

 polype, though so celebrated for its wonderful 

 works, seems to be unknown. Rumphius how- 

 ever has described that of the fungus Madrepore, 

 and recently an Italian, Vincent Rosa, whose 

 description I shall copy, another species. 



" From every cell," says he, " issues a cylindri- 

 cal animal, resembling an intestine, transversely 

 wrinkled, about half an inch long and two lines 

 in diameter, and of which the upper extremity or 

 mouth is surrounded by about twenty -two very 

 short tentacles. These animals, which are pen- 

 dent, because this madrepore is always fixed 

 under the projections of the rocks, and vibrates 

 at the will of the waves, are always of a lively 

 orange colour, they contract as soon as they are 

 touched, and they die upon being taken out of 



1 Madrepora muricata. PLATE. II. FIG. I. 



