On Coral Reefs and Islands. 345 
of considerable size. New Ireland, according to D’Urville, has 
distant reefs on part of its shores. 
‘he Admiralty Islands, farther west, are enclosed by barrier 
reefs, and beyond this group there are a few lagoon islands. 
The north side of New Guinea is mostly without coral. There 
mits, and one of them, near New Britain, and another (Vulcano), 
pare the way by pouring forth the liquid rock, and building up 
the lofty summit. Quiet succeeds, and then commences the 
work of the zoophyte beneath the sea, while verdure covers the 
exposed heights. 
We may add a few more illustrations from other parts of the. 
Coral-reef seas. 
Along the north and northwest coast of New Holland, there 
appears to be little or no coral in the Gulf of Carpentaria, while 
some extensive patches occur on the shores west of this Gulf, as 
diate, have large reefs. The Arru Group consists wholly of 
coral. ‘This sea, from Arru to the islands south a Borneo, is 
