70 COELENTERATA 



ocean travel. Many Pacific Islands are formed entirely of coral 

 rock, while the East Coast of Northern Queensland is bounded for 

 1,250 miles by the Great Barrier Reef, which extends parallel to the 

 coast at a distance from shore ranging from 10 to 90 miles. (See 

 page 65.) 



The precious corals have been known for centuries. In India, 

 coral is used as a gift to the dead to keep evil spirits away from the 

 bodies. Pure white Japanese coral necklaces are extremely valu- 

 able, those with pale pink tints bringing as much as $5,000. The 

 finest rose-pink coral brings from $400 to $600 an ounce, but the 

 ordinary red pieces bring only about $10. The small fragments used 

 in children's necklaces bring about ^oi. a string. 



References on Coelenterates 



Hargitt, C. W. 1 901. Synopsis of the Hydromedusae of North 

 America. American Naturalist, vol. XXXV. 



Trembley, a. 1744. Memoires pour servir a I'histoire d'un genre de 

 polypes d'eau douce a bras en forme de cornes. Leyden. (Re- 

 markable first study of Hydra.) 



