XX THE VOYAGE OF H.M.S, CHALLENGER. 



2. Bellonella, Gray, Proc. Zool. Soc. Lond., 1862, p. 35. 



Iphethyriis, "VV. Koch, Neue Anthozoen, Marburg, 1886, p. 3. 



Nidalia, Studer, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, 1878, p. 633. 



Cereopsis, Saville Kent, Quart. Journ. Micr. Sci., vol. xviii., 1876, pp. 397-399. 



The colony is erect, unbranched, attached by a somewhat expanded basal portion; the 

 lower part of the stem is destitute of polyps, the upper portion is slightly lobate, bearing 

 scattered, semi- or completely retractile polyps. The spicules fusiform, echinate. 

 Perhaps identical with the following genus. 



3. Nidalia, Gray, Proc.' Zool. Soc. Lond., 1835, p. 60. 



The colony is simple or branched, axis cylindrical, tough, with numerous spicules. 

 Polyps large, prominent, collected on the upper surface of a hemispherical head. The 

 spicules are described as "large conical." 



4. Paralcyonium, Milne-Edwards, Ann. des Sci. Nat., ser. 2, t. iv. p. 323, 1835. 



The colony presents two distinct portions, one, the basal portion, is dense, with firm 

 walls ; the other, the head, alone bears the polyps, and can be in part withdrawn into the 

 basal part. The polyp bearing portion is but feebly lobed. 



5. Sarakka, Danielssen, Norske Nordhavs-Exped. 1876-78, Zool. Alcyonida, 1887, 



p. 118. 



The colony is but little branched, the main axis and the branches are crowned with 

 numerous retractile polyps, with marked calyces, ribbed ; the polyps are short and tightly 

 packed together so as to leave little ccenenchyma. The whole colony is rich with spindle- 

 shaped and stellate spicules. 



6. Alcyonium, Linne, Syst. Nat., ed. 10, t. i. p. 803, 1758; Pallas {pars), Elench. 



Zooph., p. 242, 1766 ; non Halcyonium, Ehrenb., Corall. des rothen Meeres, 

 p. 56; Milne-Edwards {pars), Hist. Nat. des Coralliaires, t. i. p. 114; 

 Klunzinger, Korall. des rothen Meeres, pt. i. p. 21. 



The colony presents the appearance of variously lobed, soft masses, over the surfaces 

 of which the polyps are spread. The polyps are completely retractile. The spicules are 



