Happon—The Actiniaria of Torres Straits. 401 
Locality—Partially embedded in the mud on the fringing reef of Thursday 
Island and Warrior Island, Torres Straits, and at Port Darwin. 
Saville-Kent found numerous young ones, about an inch in length, “ enclosed, 
in some numbers, in the substance of the felt-like sheath of the parent polyps” 
in some specimens collected at Warrior Island. 
Although no pore is visible in the preserved specimen, I do not hesitate to 
allocate this fine species to the genus Cerianthus, the great state of contraction of 
the more flaccid aboral end of the body would very well make it difficult to 
definitely assert the absence of a pore in spirit specimens. 
The single example was not sufficiently well preserved to enable me to say much 
as regards the histology of this species. Thanks to the labours of Haime, von 
Heider, the brothers Hertwig, Jourdan, Danielssen, M*Murrich, and Carlgren, we 
have a very good knowledge of the minute anatomy of several members of the 
genus ; M*Murrich (‘‘ Contributions on the Morphology of the Actinozoa: 1. The 
Structure of Certanthus Amerieanus,” Journal of Morphology, Iv. 1890: p. 131) gives 
a brief summary of the literature of the anatomy of the genus, and compares his 
investigations with those of other authors. More recently (1893, p. 201) he rede- 
fines the Tribe of Ceriantheze, and describes a new species (@. vas) in which he 
could not discover any tentacles. Carlgren (1893, p. 289; 1894, p. 119) gives an 
account of C. Lloydi’, and discusses the morphology of the group. I have adopted 
his definitions which are modified from those of Hertwig. 
It is possible that this species is nearly allied to @. orventalis, Ver., from Hong- 
kong (Verrill, Proc. Essex Instit. iv. 1865, p.151; Ann. Mag. Nat. Hist. xvi. 1865, 
p. 196; Andres, 1884, Le Attinie, p. 347). 
Tribe IIL—ZOANTHEZ, R. Hertwig, 1882. 
Actiniaria with numerous perfect and imperfect mesenteries, and two pairs of 
directive mesenteries, of which the sulcar are perfect, and the suleular imperfect. 
A pair of mesenteries occur on each side of the sulcular directives, of which the 
sulcular moiety is perfect, and the sulcar imperfect ; a second similar pair occurs 
in one group (Brachycneminz); or the second pair may be composed of two 
perfect mesenteries (Macrocneminz). In the remaining pairs of mesenteries, in 
both groups, this order is reversed, so that the perfect mesentery is sulear, and 
the imperfect is sulcular. .The latter series of mesenteries are bilateral as regards 
the polyp, and arise independently (¢e. neither in pairs nor symmetrically on 
each side) in the exoccel on each side of the sulcar directives, in such a manner 
that the sulcular are the oldest, and the sulcar the youngest. Only the perfect 
mesenteries are fertile, or bear mesenterial filaments. A single sulcar, cesophageal 
groove is present. The mesoglcea of the body-wall is traversed by irregularly 
TRANS. ROY. DUB. SOO., N.S. VOL. VI., PART XVI, 30 
