52 



CORALS AND CORAL ISLANDS. 



a stem rises, with the budding cluster of polyps at its summit, 

 and the more aged, or non-budding polyps, about its sides ; and 

 the breadth of the stem depends on the size of the budding 



GONIOPORA COLUMN A, D. 



cluster. Above a case of this kind is represented, in which 



the stem is a large column. . 



The polyps, in this beautiful Pacific species, as seen, stand 

 up prominently over the coral when expanded, which is due 



