ALCYONARIA GORGONACEA 



351 



Alpheus, and may be regarded as of the nature of a gall- 

 formation.^ Faragorgia, M. Edwards ; Norwegian fjords, in deep 

 water. This genus forms very large tree-like colonies of a ruby- 

 red or white colour. It is perhaps the largest of the dendritic 

 Alcyonarians. It is dimorphic. Spongioderma, KoUiker ; Cape 

 of Good Hope. The surface of this form is always covered by 

 an encrusting sponge. Iciligorgia, Eidley ; Torres Straits. The 

 stem and branches are compressed and irregular in section. 



Fam. 2. Sclerogorgiidae. — The medullary mass forms a 

 distinct axis consisting of closely packed elongate spicules with 

 dense horny sheaths. 



Suberogorgia, Gray, has a wide distribution in the Pacific 

 Ocean, Indian Ocean, and the West Indies. Keroeides, W. and S., 

 comes from Japan. 



Fam. 3. Melitodidae. — The axis in this family exhibits a 

 series of nodes and internodes (Fig. 155), the former consisting 

 of pads formed of a horny substance 

 with embedded spicules, the latter of a 

 calcareous substance with only traces 

 of a horny matrix. The internodes 

 are quite rigid, the nodes however give 

 a certain degree of flexibility to the 

 colony as a whole. Neither the nodes 

 nor the internodes are penetrated by 

 nutritive canals, but when dried the 

 nodes are porous. 



The principal genera are: — Melitodes, 

 Vei-rill ; widely distributed in the 

 Indian and Pacific Oceans, Cape of 

 Good Hope, etc. This genus is in 

 some localities extremely abundant and 

 exhibits great brilliancy and variety of 

 colour. The branching is usually dicho- 

 tomous at the nodes. Wrightella, Gray. 

 This is a delicate dwarf form 

 Mauritius and the coast of South 

 Africa. Parisis, Verrill ; Pacific Ocean 



from Formosa to Australia but not very common. One species 

 from Mauritius. The branches arise from the internodes. 



1 S. J. Hickson, Fauna and Geog. Maldive Archip. ii. pt. i. 1903, p. 495. 



from ■^'°- ^^''- — M^^'^todes dichotoma, 

 showing the swollen nodes 

 and the internodes. 



