PREFACE TO THE THIRD EDITION. 

HIS third edition of the “Corals and Coral Islands” 
contains a full discussion of the views and arguments 
which have recently been brought forward in opposition to 
the theory of coral reefs proposed by Darwin and explained 
in the following pages. Besides this, changes and additions 
have been made in all parts of the work in order to bring 
it up to date of publication. Moreover, four new maps have 
been introduced: one, of the Central Pacific ; the second, of 
the large coral-reef region of the Louisiade Archipelago, in 
the southwest Pacific; the third, a new map of the Florida 
and Bahama coral-reef banks, from the charts of the United 
States Hydrographic Department ; and the fourth, a copy of 
part of the Hawaiian Government map of the vicinity of 
Honolulu, showing the coral reefs off the shores, and the 
positions of the many artesian borings on this border of Oahu 
that are throwing light on the thickness of the shore reef. 
The work has its value enhanced also by four new colored 
plates, one representing Actinias of the Pacific, and the others 
living corals, selected from the author’s Atlas of his Explor- 
ing Expedition Report on Zodphytes. 
JAMES D. DANA. 
New Haven, Cr., 
February 12, 1890. 
