ON THE ANATOMY OF A SUPPOSED NEW SPECIES OF 

 COENOPSAMMIA FROM LIFU. 



By J. STANLEY GARDINER, M.A., 



Felloiu of Gonville and Cains College, Cambridge. 



With Plate XXXIV. 

 IXDEX OF CONTEXTS. 



PAGE 



Preface 357 



Section I. General Anatomy of the Skeleton and Specific Description 358 



General form — Mode of growth — Peritheca — Costae — Theca — Cahce— Septa — Cohimella — ElJect 

 of boring organisms. 



Sectiox II. General Anatomy of the Polyps 360 



Composition of the colony — Peritheca and Coenosarc — The expanded polyji — The contracted 

 polyp (circular sphincter muscle) — Coenosarcal canals and mode of budding — Tentacles — 

 Retractor muscles — Stomodoeum — Mesenteries — Generative organs. 



Section III. Minute Anatomy 367 



Ectoderm (external, peristomial and tentacular) — Tentacular nematocysts (anatomy and de- 

 velopment) — Stomodoeinn — Mesenterial filaments — Mesenterial nematocysts (anatomy and 

 development) — Calicoblastic ectoderm and attachment of the structui'eless membrane to 

 the corallum — Endoderm (longitudinal and circular sphincter muscles) — Generative organs. 



Section IV. Conclusions relating to the body Layers in the Actinozoa 374 



PREFACE. 



Amongst the material very generously handed over to me by Dr Willey for 

 examination were nine colonies, with from two to twelve polyps, of a species of Coeno- 

 2)sammia, which I believe to be new, and for which I propose the specific name of 

 C. willeyi. All were obtained at Sandal Bay, Lifii, from the surfaces of reef-patches 

 on the under-side of coral masses in company with Distichopora and Stylaster. The 

 colour of the living colonies was bright red, with orange mouth-discs or peristomes. 



w. IV. 49 



