CONTENTS. 



CHAPTER I. 



CORALS AND CORAL MAKEES. 



PAGE. 



General Observations. -..-----17 



I. Polyps. 20 



I. Actinoid Polyps. -------- 21 



I. Non-Coral Making Actinoid Polyps. - 21 



II. Coral-Making Actinoid Polyps. - . ... 42 



III. Classification. ------- 61 



II. Cyathophylloid Polyps. 79 



III. Alcyonoid Polyps. ------- 80 



r7. Life and Death in Concurrent Progress. ----- 94 



V. Composition of Corals. - - - - - - 98 



II. Hydroids. ------ ---101 



III. Bryozoans. --------- 105 



IV. Algle; or, Nullifores and Corallines. .... 107 



V. The Reef-Forming Corals, and the Causes Influencing their 



Growth and Distribution. - - - - - -108 



I. Distribution in Latitude. .--..- 108 



II. Distribution in Depth. - - - - . - -114 



III. Local Causes Influencing Distribution. - - • - 119 



IV. Rate of Growth of Corals. - - - - - - 123 



