56 



CORALS 



the author made of the colour of a Brain coral in North 

 Celebes are almost identical with the descriptions of the 

 colours of Mcaiidrina lahvrinthica by Duerden in Jamaica. 



But to return to the anatomy of the polyps. Each of 

 the mouths that are found in the lamina leads into a short 

 throat (stomodaeum) which is suspended in the general 

 cavity h\ an attendant set of mesenteries. There is free 



I-'iG. :;o. — Meandriua. Nat. size 



communication between any one mouth and the cavity, 

 between the individual mesenteries of a set and the cavity 

 of the sets of mesenteries on each side of it. If, therefore, 

 we try to maintain that each mouth with its stomodaeum 

 and its set of mesenteries corresponds with a polyp, an 

 individual polyp, of such a coral as Galaxea or Favia, we are 

 met with the difficulty of determining, in the absence of a 

 limiting body wall, where one polyp ends and the others 



