CONTENTS. 



Preface ^ 



Introduction 



Adult Colony. 



External Characters 7 



Column wall 8 



Tentacles 9 



Disc and mouth 14 



Color 15 



Reproduction.. 16 



External characters on decalcification iS 



Anatomy and Histology 21 



Column wall and disc 21 



Tentacles 23 



Stomodaium 23 



Mesenteries 24 



Mesenterial filaments 29 



Skeletotrophic tissues 30 



Septal invaginations, interseptal loculi, 



and gastro-ccelomic cavity 34 



Gonads 37 



Corallum 38 



Histology 40 



Wall or theca 45 



Septa 46 



Synapticula 52 



Columella 53 



Dissepiments 55 



Epitheca and basal plate 56 



POSTLARVAL DEVELOPMENT. 



Larva 57 



Young polyp 6t 



Tentacles 65 



First cycle of exotentacles 65 



First c^cle of entotentacles 66 



Secondary exotentacles 69 



Second cycle of entotentacles and third 



cycle of exotentacles 71 



Third cycle of entotentacles and fourth 



cycle of exotentacles 73 



Mesenteries 76 



First cycle of mesenteries (protocnemes) ... 76 



Second cycle of mesenteries (metacnemes) 79 



Third cycle of mesenteries S3 



Corallum 86 



First cycle of entosepta and second cycle 



of exosepta 86 



Second cycle of entosepta and third cycle 



of exosepta 93 



Third cycle of entosepta and fourth cycle 



of exosepta 99 



Basal plate 112 



Epitheca 115 



Columella 117 



Anatomy and histology of larva and young 



polyp "9 



Young polyps 122 



References 125 



Explanation of plates 126 



Hi 



