2 
INTRODUCTION. 
these vast rings of coral-rock, often many leagues in 
diameter, here and there surmounted by a low verdant 
island with dazzling white shores, bathed on the out- 
side by the foaming breakers of the ocean, and on the 
inside surrounding a calm expanse of water, which, 
from reflection, is generally of a bright but pale green 
colour. The naturalist will feel this astonishment 
more deeply after having examined the soft and almost 
gelatinous bodies of these apparently insignificant 
coral-polypifers, and when he knows that the solid reef 
increases only on the outer edge, which day and night 
No. l. 
is lashed by the breakers of an ocean never at 
rest. Well did Francois Pyrard de Laval, in the 
year 1605, exclaim, ‘ C’est une merueille de voir 
cbacun de ces atollons, enuironne d’un grand banc de 
pierre tout autour, n’y ayant point d’artifice humain.’ 
The above sketch of Whitsunday Island, in the 
S. Pacific, taken from Capt. Beechey’s admirable 
Voyage, although excellent of its kind, gives but a 
