REPORT ON THE ALCYONARIA. XXXV 



I. Suberogorgia, Gray, Proc. Zool. Soc. Loud., 1857, p. 159. 

 Sclerogorgia, Kijlliker, Icones histiologicae, pt. ii. pp. 142, 144, 1865. 



The colonies are upright, branched, the branches sometimes anastomosing. Polyps 

 with slightly protruding calyces, which are especially distributed on either side of 

 the somewhat flattened stems and branches. The ccenenchyma is thick, and exhibits 

 longitudinal furrows on the surface of the areas which are free from polyps. The 

 sjjieules are warty spindles, and in one species bii'otate. 



2. KeroeiJc's, Wright and Studer, Archiv f. Naturgesch., Jahrg. liii. Bd. 1, p. 30. 



The upright colony branches in one plane ; the polyps form wart-like verrucas, which 

 are given ofi" mainly from two sides of the somewhat flattened branches, leaving an 

 interspace free. The spicules of the ccenenchyma are large broad spindles and poly- 

 gonal, often triangular discs. These latter are closely approximated to one another, 

 and form a pavement-like outer layer in the ccenenchyma. The calyces are thickl}- 

 covered with polygonal scales, and the tentacles also contain broad smooth spicules. 

 The whole habit, and even the character of the spicules, recall the genus Acis. 



The axis is colourless and consists of closely intercalated calcareous spindles enclo.sed 

 in a horny fibrous substance, which remains and preserves the form of the axis after 

 decalcification. 



Family III. Melitodid^. 



Melithsddx, Ridley, Rep. Zool. Coll. H.M.S. "Alert," Alcyonaria, p. 356. 

 Meiitlixaixx, KbllLker, Icones histiologies, pt. ii. p. 142. 



Melithseadm, Mopselladx, Trinellailse, Ellisdladx (pars), Gray, Cat. Lithophytes Brit Mus. 

 pp. 3, 5, 12, 24. 



Scleraxonia with a well-marked axis, which is jointed, i.e., consi-sting of alternating 

 portions of a hard calcareous and of a soft horny substance. The hard joints (internodes) 

 consist of fused calcareous spicules, with but a trace of horny substance ; the soft joints 

 (nodes) are formed of loose calcareous spicules, in a mesh of horny substance. 



Gray made of this group a number of distinct families, but these, as Ridley h;is 

 shown,^ cannot be upheld. Ridley proved that the ditterence on whirli Gray relied in 

 distinguishing Melithajidse and Mopselladaj, namel}', the penetration of the axis bj- 

 nutritive canals, is not persistent, and he refers the genera to one family, and 

 distinguishes them only by the characters of their spicules. The Melitodidie may be 

 possibly derived from the Briareidaj. Like the lower forms of the latter many ]\Ielitodidai 

 exhibit nutritive canals within the axis. Ridley thinks that siphonozooids may occur 

 as in Paragorgia beside the autozooids. An example of this dimorphism, he thinks, is 



' Loc. cil., \i. ■ioG. 



