16 



iii. TROCHOCYATHUS, Edw. & H., Martin Duncan. 

 7. Trochocyathus rotulus, n. sp. PI. ii. figs. 1, l. 



Corallum circular, shallow-saucer-shaped or almost discoidal, with a 

 margin symmetrically scallopped by the exsert septa and costse. 



No epitheca. Thin, sharply granular or spicular costse radiate from the 

 centre of the disc to the circumference, where they become very prominent. 



The septa are very thin and sharp, and have smooth surfaces. Eighteen 

 are pre-eminently large and exsert and divide the calicle into as many equal 

 chambers, each of which is again divided into four compartments by three 

 septa namely, a median shorter but hardly less exsert than the 18 principal 

 septa, and two lateral which are small and low and soon unite with the median one. 



The pali are in two perfectly independent crowns of 18 each : the outer 

 crown are large thin strongly-exsert plates, standing opposite to the median 

 septa|of the 18 principal chambers, from which septa they are remarkably 

 well isolated : the inner crown are much smaller and less exsert plates, standing 

 opposite to the 18 principal septa, from which they are separated by deep but 

 very narrow clefts. The surfaces of the large pali (of the outer crown) are 

 denticulate. 



The columella is a large irregular spongy mass with a granular and 

 papillary surface. 



The corallum is pinkish white, the soft parts are dark purple. 

 Off North Maldive Atoll, 770-960 fins. 



This singularly beautiful species has no close resemblance, except in 

 general shape, to Deltocyathus, as I have ascertained by actual comparison. 



8. Trochocyatlwis sp. 



A second species of Trochocyathus, of the same discoid shape but not 

 otherwise similar, was dredged off the Andamans at 185 f ms. As there is only 

 one dead and not quite perfect specimen I am unable to determine it. 



iv. DELTOCYATHUS, Edw. & H. 



9. Deltocyathus andamaniciis, n. sp. PI. i. figs. 5, 5. 

 Perhaps only a variety of Deltocyathus italicus (Michelin). 

 I have carefully compared the single specimen upon which this species is 

 founded with the descriptions and figures of D. italicus of Michelin, Edwards 

 and Haime, Pourtales, Lindstrom, and Moseley (the figure given by Jourdan in 

 the description of the Prince of Monaco's Zoantharia seems to be quite 



