CORAL REEFS, AND ISLANDS. 



249 



what different conditions. The terms, however, are 

 not synonymous. Coral islands are reefs that 

 stand isolated in the ocean, away from other lands, 

 whether now raised only to the water's edge, and 



FIG. 52. CORAL REEF. 



half submerged, or covered with vegetation ; while 

 the term Coral reef, although used for reefs of 

 coral in general, is more especially applied to those 

 which occur along the shores of high islands and 

 continents." 



With this preliminary definition of terms we are 



