TOILERS IN THE SEA. 247 



CHAPTER VIII. 



CORAL REEFS, AND ISLANDS. 



THE first author who collated the information 

 associated with Coral Islands, and propounded 

 a feasible theory of their structure and method of 

 construction, was the late Charles Darwin, who has 

 done so much for Biological Science during the 

 present generation. His views, propounded in full 

 in his volume on Coral Reefs, 1 were subsequently 

 subscribed to by the eminent American geologist, 

 Professor James Dana, 2 and have been generally 

 accepted ; such exception as may have been taken 

 to them being alluded to hereafter. 



Darwin classed all the phenomena of coral reefs 

 under three primary classes, Barrier reefs, Fringing 

 reefs, and Atolls, or lagoon islands. These may be 

 briefly described, in Mr. Darwin's own language, as 



1 " Structure and Distribution of Coral Reefs," by Charles 

 Darwin. London, 1851. 



* "Corals and' Coral Islands," by James D. Dana, LL.D. 

 Popular edition. London, 1875. 



