VI 
PREFACE. 
are to be found in previous works. Much the larger part of these spe= 
cies have been studied from specimens. The names of those thus ex- 
amined are distinguished by a ^ in the Index. 
The subject of Corals, in this volume, is treated of exclusively in a 
zoological point of view. The geological questions with regard to the 
formation and structure of coral-reefs and islands, will come up for dis- 
cussion in the author’s Geological Report.” 
JAMES D. DANA. 
New Haven, January, 1859 . 
