1892.] UR. S. J. HICKSON ON ALCYONARIA STOLONIFERA. 595 



Perceval Wright, and Studer, but a renewed investigation of the 

 genera belonging to the suborder has convinced him that the pro- 

 posed classification is perfectly justified. The suborder Stolonifera 

 may be defined as follows : — 



Colonial Alcyonaria with a membranous or ribbon-like stolon. 

 Mesogloea poorly developed. Polyps either entirely free from one 

 another except at their bases, or connected by horizontal platforms 

 (Tubipora) or connecting tubes {Clavularia viridis and the fossil 

 Syringopora). Skeleton composed of calcareous spicules which may 

 be joined together to form firm tubes, or free from one another, or 

 absent. In some cases the body-walls supported by a horny 

 secretion. 



The suborder Stolonifera contains two families : Tubiporidee and 

 Clavulariidffi. 



The family Tubiporidse contains one genus : Tuhipora. 



The family Clavulariidse contains four genera : Olavularia, 

 Cornulciria, Stereosoma, and Sympodium, and probably Syringopora. 



The genus Cornularia may be defined as follows : — 



Clavulariidse without spicules. Stolons with a simple cavity. 

 Polyps retractile. The basal parts of the polyps and stolon protected 

 by a horny secretion. 



The genus Clavularia may be defined as follows : — 



Clavulariidse with a membranous or retiform creeping stolon 

 into which the polyps cannot be completely retracted. Spicules 

 usually present. No horny secretion of the ectoderm formed. 



The genus Sympodium may be defined as follows : — 



Clavulariidse with a thick plate-like stolon into which the polyps 

 may be completely retracted. 



The genus Stereosoma may be defined as follows : — 



Clavulariidse forming small colonies, consisting of stiff non- 

 retractile polyps situated at considerable intervals from one another 

 on a thick plate-like stolon. Tentacles non-retractile. Pinnse few 

 and widely separated from one another. Spicules absent. 



Rhizoooenia, Sarcodicfyon, AntheUa, Gymnosarca, Cyathopodium, 

 and Oornulariella can no longer be retained as separate genera, as it is 

 impossible to separate them from the genus Clavularia. The species 

 of these genera therefore become species of Clavularia. 



The following new species of Stolonifera are described : — 



Stereosoma celeiense, from the shore reefs of Talisse Island, 



North Celebes. 

 Clavularia garcice, from Diego Garcia, shallow water. 

 Clavularia reptans, 5-20 fathoms off Talisse Island, N. Celebes. 

 Clavularia celebensis, shallow water, Talisse Island, N. Celebes. 



The following species previously named by the author in the 

 Proc. Royal Society of Victoria are described in detail for the first 

 time: — 



Clavularia australiensis, varieties A & B. 

 Clavularia ramosa. 

 Clavularia flava. 



