NULLIPORES AND CORALLINES. 137 



beauty, for when alive, the little inhabitant waves a plume 

 of brilliantly-coloured feathers its breathing apparatus 

 from the door of its home. 



The nullipora is one of the numerous sea-plants, like the 

 corallines, which take up large quantities of carbonate of 

 lime, and though not hard, as the latter are, is very tough. 

 Both grow in most luxuriant profusion among the Bermuda 

 reefs, and are of ^reat beauty. As we know it, the coralline, 

 with its hard, jointed stems, is either pale pink or lilac, or 

 more often bleached to the whiteness of bone by sun and 

 wind ; but in the Bermudas the prevailing colour is green, 

 which varies from a bluish to a grass-green tint, with here 

 and there a tuft of plum colour, and white is rare. One 

 species of nullipore is of a brilliant peach colour, and has 

 thin, stiff, moss-like branches, the tips only of which are 

 alive, and another grows in lichen-like sheets. 



Both plants take up so much lime, that they are capable 

 of forming masses of calcareous matter two or three feet thick 

 by their successive growth and decay. 



It had been supposed, until within the last few years, 

 that the depths of the ocean were devoid of both animal 

 and vegetable life, but the voyage of the Challenger has 

 shown that this is a mistake. Only an infinitesimal portion 

 of the ocean floor, at depths over 2,500 fathoms,* has 

 even now been explored, we must remember; but so far 

 as this has been done, animal life is found everywhere 

 though it is less plentiful in extreme depths while plants, 

 though stragglers may be found here and there, are prac- 

 tically limited to depths under 100 fathoms. Sponges exist 

 * Three miles. 



