294 Proceedings of the ttoijal trish AcademiJ. 



of concentric laminae, which consist of a homy substance iiupreguated with 

 some form of calcareous matter. The surface is marked l)y longitudinal grooves, 

 which correspond in number \.a the inner series of longitudinal canals, and 

 therefore diminish from the base upwards. Sometimes two larger than the 

 others are to be seen, and these represent the position of the two main 

 canals. The spicules consist of the usual Juncella types, and include clubs, 

 double-wheels, and double-stars. The colour varies from pure white, through 

 orange, to dark red. 



XI. — Juncella gemmacea. Figs. 15-19. 



Gorgonia gemmacea Valenciennes, MSS. dans la Coll. du Mus. Paris. 



Verriuxlla „ Milue-Edwards and Haime, xxvi., p. 185, B 2, f. 7. 



JiDiceila „ KoUiker, xxiii., p. 140, t, 14, f. 4. 



„ „ "Wright and Studer 1., p. 158, PI. xxxiv, fig. 13. 



„ „ var. Ridley, xxxii., p. 241. 



„ „ Studer xxx\'ii., p. 117. 



„ Thomson and Russell, xliii., p. 162. 



Elliiella „ Gray, xii., p. 26. 



ElliseUa macuiaUi (pars) Wright and Studer, 1. 



Junctlla elongata var. Ridley xxxiiL, p. 346. 



Valenciennes in 1855 established this species to include a specimen in the 

 Natural History Museum in Paris, under the name of Gorgonia gemviacea 

 (MSS. dans la collect, du Museum Paris). 



In 1857 Milne-Edwards and Haime tefen-ed the species to the genus 

 VeiTucella, and defined it as follows : — 



" Polj'pieroide dont les branches, assez nombreuses et cylindriques, se 

 dichotomosent de loin en loin, et s'^cartent beaucoup entre elles ; les 

 ramuscules terminaux allonges. Coenenchyme trcs-friable, d'un jaune 

 ferrugineux k la surface et blancli&tre puis de I'axe. Verrues caliciferes tres- 

 saillantes, arrond^es et dressees centre la tige." 



They give a very good figure, showing the mode of branching. In 1865 

 KoUiker removed the species from the genus Verrucella to Juncella, and 

 noted for the first time that " clubs " occurred amongst the spicules just as in 

 J. juticea. He gives two figures — (1) a club-shaped spicule (woodcut 19, 1); 

 (2) a cross-section of the axis (Pl. xia', fig. 4). 



Gray in 1870 referred this species to the genus ElliseUa with no apparent 

 justification. (See our Historical Note.) This change, however, was not 

 recognized by any subsequent authors, so that Ridley in 1884 identified 

 some specimens from Queensland, under the name of J. gemmacm, and 



