SOLITARY CORALS. 209 



In other words, the formation of a new cycle of entoccelic septa has progressed more 

 rapidly at the two directive ends than at the sides, and the sequence is therefore 

 different from that ohserved by Duerdex in Siderast/rcsa radians. 



This specimen is in many respects intermediate between Semper' s Rhodopsammia 

 carinata and R. parallela, and I am inclined to think that these two and R. amema 

 are only varieties of one species. The Ceylonese specimen agrees with R. parallela 

 in having vertical inner edges of the primary and secondary septa, in the costse being 

 of equal size, in the presence of a fifth incomplete cycle of septa, and in the depth of 

 the fossa. In all these respects it differs from carinata, but such characters are 

 clearly variable. The calice is less compressed and more regularly oval than in 

 Semper's figures of parallela, but Fowler (14) gives a figure of the calice of this 

 species in which the difference between the longer and shorter axes is even less than 

 in the specimen here described, and the septal arrangement is almost identical. 



Balanophyllia cumingi, M. Edwards and Haime (36) Plate II., figs. 7 and 7a. 

 Rhodopsammia ovalis, Semper, ' Zeit. fur Wiss. Zool.,' xxii., p. 262, 1872. 



There are three specimens in Professor Herdmax's collection, of which one, from 

 deep water oft' Galle, so closely agrees with M. Edwards and Haime's description 

 and figure of B. cumingi that T have no hesitation in referring it to this species. It 

 is somewhat larger than the type specimen (the height being 12 millims., the calice 

 19 millims. x 12 millims.) and the fifth cycle of septa is well developed and nearly 

 complete. The second specimen is from Trincomalee and is a small colony, or rather 

 an aggregation consisting of three dead and decayed corallites, one small and one 

 large living corallite. Of the living corallites the larger measures : height 30 millims., 

 calice 19 millims. x 12 millims., depth of calice 12 millims. Smaller corallite : height 

 12 millims., calice 8 millims. x 6 millims., depth of calice 5 millims. The larger 

 corallite is identical with the specimen of B. cumingi, from Galle, in septal 

 characters, the columella, and the costee, differing from it only in being longer and 

 turbinate in shape with a narrow base, whereas the Galle specimen is short with a 

 broad base. The septal arrangement is shown in fig. 7a, and it agrees very exactly 

 with Semper's description of Rhodopsammia ovalis. The tertiary septa are continued 

 below into the columella, but, as the figure shows, their lower ends converge distinctly 

 towards the secondary septa. The " quaternaries " are inserted very low down on 

 the tertiaries and the quinary cycle is nearly complete, but in the two lateral systems 

 three of the quaternaries adjoining the secondary septa are not bifurcated, nor is the 

 quaternary adjoining a secondary in one of the remaining systems. The smaller 

 corallite in the Trincomalee specimen has a nearly circular calice. The six primary 

 septa are conspicuously larger than the others and pass straight to the columella. 

 The secondary septa are joined just above the columella by the " tertiaries," and the 

 latter bifurcate in all but two instances and a new cycle of entoccelic septa is formed 

 in the bifurcations. This shows that the secondary septa have been formed in the 



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