Haddon and Shackleton — Actinice : I. Zoanthece. 677 



We have named tliis species in honour of Dr. Coppinger, who, when surgeon on 

 board H.M.S. ''Alert," collected some marine zoological specimens from Torres 

 Straits.* 



Body-ivall (Pis. Lxn., lxiv.). — The wall of the column is bounded exter- 

 nally by a distinct cuticle. Between this cuticle and the ectoderm lies a thin 

 peripheral layer of mesogloea, the " subcuticula" of Andres and M'^Murrich. The 

 ectoderm forms an almost continuous layer, but is crossed by numerous delicate 

 strands of mesoglcea, which imite to form the peripheral layer. In addition to the 

 ordinary columnar cells, nematocysts of an oval shape are present. Numerous 

 branching and anastomosing canals arise from the ectoderm, and run through the 

 mesogloea, generally in a radial direction. They vary greatly in size. Sometimes 

 they run along close to the endoderm, but we have never observed any connexion 

 with it. Many of these canals pass into the mesenteries, where they form large 

 sinuses. Nematocysts, similar to those in the ectoderm, are found in these canals. 

 The mesogloea, which constitutes the chief thickness of the body-wall, is homoge- 

 neous and clear, and is permeated by the usual minute cells, which are drawn 

 into fine protoplasmic strands. These have a radial direction, and extend right 

 across the mesogloea, from endoderm to ectoderm. The endoderm is crowded 

 with zooxanthellse. There is a slight diffuse endodermal muscle. 



Capitulum. — The ectoderm becomes continiious in the capitulum, and in 

 contracted specimens is thrown into deep folds. Nematocysts are very 

 numerous. 



BpUncter muscle. — The double sphincter muscle is a powerful one, the upper 

 portion being slightly shorter than the lower one (PL lxiv., fig. 3). It consists 

 of numerous irregularly shaped cavities, the mesogloea being arranged in com- 

 plicated plaitings. 



Tentacles (PL lxiv., fig. 2). — The ectoderm of the tentacles is normal and 

 ciliated. The nuclei form a distinct central band in section. Outside the band 

 are numerou,s, small, thin nematocysts, whilst between the band of nuclei and the 

 mesogloea small irregular cells may be discerned, which are probably nerve cells. 

 There is a diffuse ectodermal muscular layer. The fibres, which are longitudinal 

 in direction, are supported on simple plaitings of mesogloea. The mesogloea 

 forms a thin layer without canals or enclosures of cells. The endoderm, which is 

 crowded with zooxanthellse, is very thick, so that the lumen of the tentacles is 

 almost obliterated. Nematocysts, similar to those found in the capitulum and 

 other parts of the ectoderm, are abundant in the endoderm of the tentacles. The 

 endodermal muscle fibres are circular in direction. 



* See " Eeport on the Zoological Collections made in the Indo-Pacific Ocean during the Voyage of 

 H. M. S. 'Alert,' 1881-1882" (1884). 



