25 



The surface of the branches is quite smooth to the naked eye, but round 

 that part of the margin of the cups that is not immersed in the base of their 

 successor faint traces of costae may sometimes be seen with a lens. 



The cups are circular, deepish in the living state, and empty-looking 

 owing to the scarcity and tenuity of the septa. 



The septa, which are not at all exsert, are in six systems and three cycles, 

 but those of the third cycle need careful looking for with a lens. Even those 

 of the second cycle are often small and inconspicuous. Those of the first cycle 

 are always plainly visible to the naked eye : even they are often inconspicuous 

 near the mouth of the cup, but deeper down, where they meet, they are pro- 

 minent. 



There is no columella : the septa often barely meet. 



As growth proceeds, several more or less parallel branches may fuse to- 

 gether, not in a solid mass but by a superficial crust, and in this way hollow 

 branching trunks result, which give a lodging to a large species of polychaBte. 

 Furthermore, as these trunks age, the calices on their surface fill up, and at 

 last show as mere smooth round depressions. 



The colour of the fresh corallum varies from light pinkish brown to 

 cinnamon. Diameter of calicles 3 to 4 millim. 



A large number of branches was dredged off the Travancore coast at 

 430 fms. 



This species seems to be nearest to Lophohelia Candida Moseley, which 

 was dredged by the " Challenger " in the West Indian Seas at 450 fms. 



xi. AMPHIHELIA, Edw. & Haime, Martin Duncan. 

 20. Amphihelia (Diplohelia) moresbyi, n. sp. PL iii. figs. 4, 4. 



Corallum proceeding by regular alternate-distichous, sometimes dichotom- 

 ous, subterminal gemmation. 



Surface of branches quite smooth to the naked eye, extremely faintly 

 granular and striated under the lens : at the very margin of the calicles are 

 short costal ridges corresponding with the septa. 



The calices are sub-circular and deep, and their cavities are very little 

 encroached upon by the narrow septa : these are in six systems of three com- 

 plete cycles, are almost all of one size, and are slightly exsert ; their surfaces 

 are roughened by small spicules. 



There is a deep-seated spongy-trahecular columella of some size, but there 

 are no pali. 



Colour white. Diameter of calices 4 millim., or a little less. 



4 



