180 THE OCEAN WORLD. 



Coral, although it differs widely in structure from the precious Coral, 

 is found in the Mediterranean and also in the tropical seas. In 

 2, Fig. 62, we see a portion of a branch magnified, so that the reader 

 may be able to appreciate the form of the polyp cells. 



The species formerly referred to in this genus as Oculina flabelli- 

 formis, now bearing the name of Stylaster flabelliformis, which is 

 represented in Fig. 63, will give an excellent idea of these arborescent 

 madrepores. The polypidom is in the form of a fan, with many very 

 unequal branches ; the larger branches are smooth, the middle-sized 

 are covered with small points. This fine madrepore is found in the 



Fig. 64. Astreopora punctifera (Lamarck). 



seas which surround the Isle of Bourbon and the Mauritius, fine 

 examples of which are to be seen in almost all large public museums. 



How diversified are the forms of aquatic life ! " Nature revels in 

 these diversities," to paraphrase the saying of one of the ancient 

 kinjjs of France. Here are animals, the skeletons of which might 

 have been designed by a geometrician. They are called Star Corals 

 (Astrea). Their resemblance to a perfectly regular star was too 

 striking to escape the observation of the naturalist ; but the organisa- 

 tion of these creatures of the ocean is far from being rigorously 

 regular, for Nature rarely employs perfectly straight lines, giving an 

 evident preference to circles and waving lines. 



The Astreidcz form an immense section of the aporous Madre- 



