PREFACE. 



The object in view in the preparation of tins work has been 

 to present a popular account of " Corals and Coral Islands," 

 without a sacrifice of scientific precision, or, on the main 

 topic, of fulness. Dry details and technicalities have been 

 avoided as far as was compatible with this restriction, explana- 

 tions in simple form have been freely added, and numerous 

 illustrations introduced, in order that the subject may have its 

 natural attractiveness to both classes of readers. 



1 have opened the volume with a chapter on " Corals and 

 Coral Makers,"" describing, under it, the forms and structure 

 of Polyps ; how they Hve and grow and hold their own in a 

 world of enemies ; how coralmaking species secrete their 

 coral ; how they multiply, and develop their large clusters, 

 spreading leaves and branching forms, so much like those 

 among plants ; and in what seas they thrive, and under what 

 conditions produce the coral plantations. 



All this is prefatory to the following part of the volume on 

 Coral Reefs and Islands, which comprises a description of the 

 features and structme of these reef-formations, an account of 

 their mode of accumulation and increase, and a discussion of 

 the origin of the included channels and lagoons, and of the 

 distribution of reefs, together with a review of the facts with 

 reference to their geological bearing. 



