THE MADREPORE, 109 



at all clustered, but scattered at irregular distances. I 

 obser\^ed them to be affixed to perpendicular and over- 

 hanging surfaces, but in no case on a diagonal or a 

 horizontal one with an upward aspect, not even in 

 the remotest part of the cavern. All that I saw were 

 left exposed by the receding tide, though in any but a 

 spring-tide they would all have been constantly cover- 

 ed. I afterwards found a few more on the sides of 

 pools in the rocky ridges, several feet above low-water 

 mark. 



In general the terminal half shewed only the 

 white radiating plates of stone, within which the animal 

 was so completely drawn that the eye could not detect 

 the delicate membrane which enveloped them. From 

 some of the largest, however, particularly those which 

 were affixed to overhanging surfaces, there depended a 

 shapeless mass of transparent jelly, extending in some 

 cases to 1 J inch. This, however, was speedily retract- 

 ed when the Coral was rudely touched. I procured a 

 dozen specimens, for the friable slate was easy to 

 dislodge ; but in many cases the Coral itself was 

 detached from its base during the process ; and of 

 some I found that I could detach them, and even break 

 to pieces the texture of stony plates, wdth my fingers. 

 I brought home and put in sea- water all that I obtain- 

 ed but those only which remained attached to a piece 

 of rock expanded their tentacles Those which had 

 been broken from their bases contented themselves 

 with protruding the tips of these organs around the 

 oral disk. 



But after some weeks those whose bases had been 

 detached opened as freely as those which had the 



