8 PREFACE. 
on Coral Reefs and Islands has been greatly extended by the 
addition of facts from numerous sources. The authorities 
cited from are stated in the course of the volume, and need 
not here be re-mentioned. I have occasion, however, for special 
acknowledgments to our excellent Yale Zodlogist, Professor 
A. E. Verrini, who now stands first in the country in the de- 
partment of Zoéphytes. Through his recent memoirs on the 
subject, and also by his personal advice, I have been greatly 
aided in acquainting myself with the present state of the sci- 
ence :—my own special labors in this branch of zoélogy having 
ended in 1850, when both the Reports, referred to above, had 
been published, and the last of my Expedition departments— 
that of the Crustacea—forced my studies in another direction. 
The illustrations of the following pages have been drawn 
mainly from my Expedition Reports. Those not my own are 
from the works or memoirs of Gossr, Ménrus, VerriLL, Pour- 
TALES, L. Acassiz, A. Acassiz, Swirr, Enwarps and Hare, 
Wixes, and Harrr. In addition, the volume is indebted for 
a few cuts to the beautifully illustrated popular works, ‘ Le 
Monde du Mer” and “ La Vie et les Mceurs des Animaux;” 
but nearly half of these were engraved from my plates. The 
sources of all the figures are given in the List of Illustrations. 
James D, Dana. 
New Haven, Conn., February 12, 1872. 
