272 Proceedings of the Royal Irish Academy. 



If a preparation of spicules be made in the manner described, there 

 should be no difficulty in at once deciding whether or not the type described 

 and figured, as a " club," is present or not. (See figs. 4, 14, 23, and 26.) 

 On the other hand, figs. 114, 115, 116, and 118 give a good idea of the " long- 

 spindle type " and its proportion to the small double-club. Any of the figures 

 given of the various species of Scirpearia — e.g. figs. 27, 31, or 65 — will at 

 once mark these off as quite distinct from the other two types. 



YI. — P0.SSIBLE Affinities of the Qorc.onellidae. 



In the "Challenger" Keport on the Alcyonaria (vol. xxxi.), Wright and 

 Studer divide the Qorgonacea into two large sections : — 



I. Scleraxonia, and 

 II. Holaxonia. 



In tlie Scleraxonia they recognize the Sclerogorgidae as a distinct family, 

 with the following cliaractera : — " In the representatives of this family a 

 distinct axis is formed of a tissue consisting of numerous closely intercalate<l 

 elongated spicules, with dense lioniy .shields. The axis is surrounded by 

 longitudinal canals, into which there open the reticulated coenenchymatous 

 canals uniting the polyps." 



In the Holaxonia there occurs the family GorgoncUidae, in which " the 

 axis is lamellar and calcareous, but retains its shape after the extraction of 

 tlie calcareous matter." 



The nature of the *' calcareous matter " is, however, not specified, so that 

 it is verj- diHicult to interpret exactly what may have been the opinion of 

 these authors. 



In "A Treatise on Zoologj'," part 11., Bourne divided the Alcyonaria 

 into five large orders as follows: — 



(1) Stolonifera. 



(2) Alcyonacea. 



(3) Pseudaxonia. 



(4) Axifera. 



(5) Stelechotokea. 



Tlie Stolonifera, Alcyonacea, and Stelechotokea are sufficiently distinct, 

 and most certainly have no connexion with the Gorgonellidae, so that any 

 further reference to them would be superfluous. 



The Pseudaxonia have been described as " Synalcyonacea forming upright, 

 branched colonies. The zooid cavities short ; the zooids embedded in a 

 coenenchyma containing ramifying solenia and numerous spicules. The 



