60 A NATURALIST ON DESEET ISLANDS. 



and it was obvious from the very patchy nature of the 

 colonies and the riddled surface of the coral rock elsewhere 

 that even they had a hard struggle to exist. On the rough 

 uneven surface of these coral platforms, life indeed existed 

 for them along no easy lines. They were buffeted by 

 waves, constantly injured by the impact of coral debris 

 or the deposition of coral sand. The very rock, which 

 was the produce of their own secretions, was being exposed 

 to the solvent and disintegrating action of the water, 

 the borings of worms and moUuscs, and the parasitic like 

 growths of nuUipores, or even of other forms of coral. 



Very different was it if we crawled to the edge of our 

 submarine island, and with the aid of a fish glass peered 

 over into the depths below, where all was still and at peace, 

 or comparatively so. Jutting out from the sides of the rock 

 we could, for instance, see another coral colony growing 

 some five feet down. This colony belonged to another 

 species of Porites. It grew as long, slightly branching 

 and finger like processes of a bluish mauve colour. Each 

 long process was smooth and rounded and about a foot 

 long. The whole colony was firmly rooted to the rock ; 

 so that when we passed the boat hook round its tough 

 base we had the greatest difficulty in pulling it up. Nothing 

 could have looked or felt so little like what one had 

 generally thought of as coral. It felt soft ; one 

 could bend each long finger-like branch almost as 

 easity as an asparagus shoot ; and with one slash of the 

 knife slice them through and through. But again one 

 could easily appreciate that it was only by reason of its 

 position in the still and sheltered water beneath the over- 

 hanging rock that the form of it was possible. In other 

 places this species, or one remarkably like it, grew as 

 tufts in the coarse sand. 



A little further down was another branching mass of 

 coral — the magnificent tree-like form of a madrepore. 

 It grew in a great spreading tuft, like a splendid chocolate- 

 brown fern, or the flat branching antlers of a stag. Again 

 we lowered the boat hook and passed it round the base 



