20 



Septa elegantly echinulate, in six regular systems and four complete cycles : the primaries 

 which are the largest and most exsert, reach the columella ; the quaternaries unite with the 

 tertiaries near the calicular margin, and the tertiaries with the secondaries near the columella. 



At first sight the pali seem to be in a single crown situated opposite the secondary 

 septa, but broad paliform lobes are also present opposite the tertiaries at the point where the 

 quaternaries unite with them. The pali opposite the primaries are small denticles not distin- 

 guishable from the columella. 



The columella consist of eight or ten denticles including those opposite the primary 

 septa, which perhaps are pali. 



Height of corallum 3 millim. 

 Diameter of disk 5 „ 



22. Deltocyathus magnificus Moseley. 



Deltocyathus magnificus Moseley, Proceedings of the Royal Society, 1876, p. 662, and Challenger 

 Deep Sea Madreporaria, p. 147, pi. IV. üg. 10, pi. XIII. figs. 1, 2. 



Stat. 95. 5°43'.5N., iiq°4o' E. 522 m. 5 Ex. 



[Stat. 96. S. E. Side of Pearl Bank, Sulu Archipelago 15 m. 7 Ex.] 

 Stat. 166? 2°28'.5 S., 1 3 1 ° 3'. 3 E. 118 m. 1 Ex. 



The specimen from Station 166? is a magnificent one, perfect, and over 28 millim. in 

 diameter. Those from Station 95 are dead, broken, and discoloured. Also from Station 45 

 (7 24'S., 1 18 1 5'. 2 E., 794 m.) are some fragments that possibly belong to this species. 



Distribution. East Indian Archipelago. 



22a Deltocyathus magnificus var. sitlucnsis nov. 



Stat. 95. 5°43'.5 N., U9°4o' E. 522 m. 2 dead Ex. 

 Stat. 100. 6°ii' N., I20°37'.5E. 450 m. 4 dead Ex. 



These six specimens resemble the typical Deltocyathus magnificus in everything except 

 that the septa of the fifth cycle, instead of uniting with one another over those of the fourth, 

 are either free in all their extent or merel j' touch those of the fourth. 



Corallum discoidal. The horizontal wall is costate, the costae being all of one size and 

 radiating from a central scar. 



The septa are in six regular systems and five complete cycles, those of the last cycle 

 being lower and very much thinner than those of the other four which, in the largest specimen, 

 are of nearly equal size, so that the septa are alternately large and small. All the septa are 

 about equally exsert at the edge of the disk. 



The septa of the first cycle are independent throughout their course to the columella : 

 those of the fourth cycle unite over and with those of the third, and those of the third unite 

 over and with those of the second. At all these points of union there are paliform thickenings, 

 and smaller paliform nodules are present at the ends of the primary septa. The septa are 

 much worn but were evidently echinulate. 



The columella is a spreading, encrusting, spongy mass. 



The diameter of the largest specimen is about 14.5 millim. 



