No. L— A EEVISION OF THE RECENT COLONIAL ASTR^ID^ 

 POSSESSING DISTINCT CORALLITES. 



(Based on Material from the Indo-Pacific Ocean and the Collections of Paris, Berlin, 



Vienna, Copenhagen, London and Glasgow.) 



By George Matthai, B.A. 

 {Research Student of Emmanuel College), Zoological Laboratory, Cambridge. 



(Communicated by Prof. J. Stanley Gardiner, M.A., F.R.S., F.L.S.*) 



(Plates 1— 38t.) 



Read 18th June, 1914. 



CONTENTS. 



I. INTRODUCION 



II. ANATOMY OF THE POLYPS. Methods— Body-layers— Mesoglrea—Oalicoblastic Layer of 

 Ectoderm — Dissepiments and Polypal Growth — Nematocysts (Types I, II, III) — Nervous 

 System — Endodermal Musculature — Ectodermal Musculature — Oral Disc — Column Wall — 

 Edge Zone and Ooenosarc — Tentacles — Stomodseum — Mesenteries — Mesenterial Filaments — 

 Acontia and Cinclides — -Reproductive Organs — Zooxanthellse ...... 



III. CLASSIFICATION. Gemmation and . Fissiparity— Astrseidse with Distinct Corallites— 

 Summary of Characters — Keys to Genera (Polyps and Corallum) ..... 



PAGE ' 



2 



6 

 33 



* [Mr Matthai wishes me to add in a footnote the part I have played in the preparation of this 

 Report during the three years that he has worked in my Department. We originally intended to 

 examine Gyphastrea in collaboration, and indeed we worked together on this genus for over six months, 

 before I retired solely owing to pressure of other work. Since then I have constantly seen Mr Matthai 

 and he has demonstrated to me on his sections and specimens most of his facts ; we have discussed 

 these facts but the deductions therefrom are entirely Mr Matthai's, though with most I concur. The polyp 

 sections were cut by the aid of my laboratory attendants, and will remain with me or be deposited 

 in some place where they will be available for future research by serious students; sections of. coral 

 were also cut professionally. Mr Matthai in the course of his research re-examined all my polyp material 

 of Uoenopsammia, Flabellum, etc. From time to time I have been in communication with Professor 

 G, C. Bourne, Dr Wayland Vaughan, Professor S. J. Hickson and Mr Cyril Crossland. In particular 

 Professor G. C. Bourne favoured me with a series of most valuable suggestions, as a result of which 

 Mr Matthai spent three months in re-examining his polyp material. A further study of the cytology 

 of the polyps, or some species of coral polyp, is requisite, but it should be undertaken with fresh 

 material. — J. Stanley Gardiner.] 



t The Royal Society has generously given a grant of £70 from their Publication Fund towards the 

 cost of the plates which accompany this paper. 



SECOND SERIES— ZOOLOGY, VOL. XVIL 



