SHALLOW-WATER FAUNA OF THE TROPICS. 67 



animals to which the Anemones belong. Another 

 family of Polyps called the Clavulariidse belong- 

 ing to the Alcyonarians has some species which 

 make no skeleton of calcium carbonate. An illus- 

 tration of one of these is given below (Fig. 22). 

 Another species, called Clavularia viridis, which 

 forms a few spicules in its body-wall, has a very 

 wide distribution in the East Indies. In some 

 places patches of it may be seen several square 



FIG. 22. Stereosoma, one of the Clavulariidae. 



yards in extent, and the crowds of little Polyp 

 heads with their eight-feathered tentacles waving 

 to and fro with the pulsations of the tide, is a 

 sight that excites immense interest and admira- 

 tion in the mind of the observer. 



One word more about the Corals. Where they 

 are so abundant in number and species, where 

 rocks hundreds of miles in extent are mainly 

 composed of their shells and skeletons, it might 



