266 CORALS AND CORAL LSLANDS. 



patches about their shores, although affording long lines of 

 coast for their growth. In the China Seas there are numerous 

 shoals, banks, and island reefs of coral. Moreover, shore 

 reefs occur about Loochoo, and the islands between it and 

 Formosa. But the whole eastern coast of China appears to be 

 without coral. Quelpaert's Island, south of Corea, in 34° N., is 

 described as having coral about it ; and this has been con- 

 firmed by late information. 



Why should the reefs of the East India Archipelago be so 

 limited in extent, and large parts be almost destitute, notwith- 

 standing their situation in the warmest seas of the ocean and 

 in the most favourable region for tropical productions ? We 

 are not prepared for a full answer to this inquiry ; for it would 

 demand a thorough knowledge of the shores, as well as of the 

 currents, and of the former and present condition of volcanic 

 fires. From personal observation we may reply satisfactorily 

 as far as regards part of the southern half of the east coast of 

 vSumatra. This coast is low and sandy, or muddy, and thus 

 affords the most unfavourable place for zoophytes. A strong 

 current sweeps through the Straits of Banka, which keeps the 

 water muddy, and the shores in constant change. The same 

 cause may operate on the coasts of other islands, but we can- 

 not say to what extent. 



The East Indies have been remarkable for their volcanoes, 

 exceeding, for the area, every other part of the world ; and this 

 fact must have had influence on the formation of coral reefs, 

 though there are not data for fixing the extent of the influence. 

 Of the thousand vents which have been in action, several still 

 make themselves felt over wide areas. The Sooloo Islands are 

 about one hundred in number, and nearly all are pointed with 

 volcanic cones ; and while some have the broken declivities that 

 are marks of age, others have regular slopes, as if but just now 

 extinguished ; a dozen of these cones may sometimes be seen 

 on a single island. These volcanic peaks often rise out of the 

 sea, as if their formation had begun with a submarine erup- 

 tion. In a region so extensively and so recently igneous, the 

 coral polyps would have found little chance for growth, until 



