XVI 



THE VOYAGE OF H.M.S. CHALLENGER. 



15. CalUpodium, Verrill, Trans. Connect. Acad., vol. i., 1868, pt. 2, No. 6, p. 455. 



The colony has a firm, more or less thickened coenenchyma, either broadly expanded 

 or in narrow stolons. Polyps rather large, with rounded verrucae sometimes scattered, 

 sometimes crowded; wholly retractile, in contraction forming an eight-rayed figure. 

 Spicules irregular, some short spindles, others double clubs and crosses. 



16. Pseudogorgia, KoUiker, Verhl. d. phys.-med. Ges. Wiirzburg, N. F., Bd. ii. Heft, 

 i. p. 12. 



The colony in this very remarkable form is upright ; nearly one-half of the main axis 

 is destitute of polyps, while on the upper portion these are arranged in two rows on 

 either side of the stem, which is flattened about its centre and becomes cylindrical 

 towards the summit. The polyps are completely retractile within the coenenchyma, 

 leaving but slight verrucse. The main axis itself is formed by an axial polyp, around the 

 sides of which the lateral polyps have budded. The spicules are broad warty spindles. 



The natural relationships of some of these forms may be indicated in the following 

 scheme, without, however, claiming for it any great value from a phylogenetic point of 

 view. 



Haimeidae 



Cornularia 



I 

 Clavularia 



Sarcodidyon 



I 

 CalUpodium 



Telesto 



I 

 Ccelogorgia 



Syimpodium Erythropodium Holaxonia 



I 

 Briareid^ 



Cornulariella 



I 

 Gymnosarca 



Pseudogorgia 



I 

 Pennatulacea 



Sderantheh'a 



I 

 Anthopodium 



Rhizoxenia 



I 

 Antlielia 



Xenia 



Cyathopodium 



I 

 Tuhipora 



Family III. T u B i p o R i D^. 



TuUporidx, Verrill, Proc. Essex. Inst, vol. iv., 1865, p. 148, 

 Tuhiporina, Elu-enberg, Corall. des rothen Meeres, p. 55. 

 Tubiporinx, Milne-Edwards, Hist. Nat. des CoraUiaires, t. i. p. 130. 

 Tuhiporida, v. Koch, Morpli. Jalirb., pp. 474, 475. 



The colonies form series of completely calcified coral stocks, consisting of numerous, 

 approximately parallel, calcareous tubes; these tubes arise from the coalescence of the 



