THE ANATOMY OP THE MADREPOEAKIA. 419 



classed, as does Amphihelia to its family the Oculinidse ; that 

 is to say, it is possible that in the former, as certainly in the 

 latter, the peripheral lamellar, which are found in such allied 

 genera as Rhodopsammia and Lophohelia respectively, have 

 been obliterated and functionally replaced by a radial out- 

 growth of coral from their points of attachment. The tra- 

 becular of coral to which the mesenteries are attached are of 

 course not in this genus any more than in Amphihelia to be 

 regarded as true costar, since they bear no relation to the septa, 

 and are a simple outgrowth from the theca. 



In several respects Stephanophyllia exhibits a resemblance 

 to the Fungia recently described by Bourne (' Quart. Journ. 

 Micr. Sci.' xxvii). The plano-convex shape of the coralluru, 

 and the correlated basal position of the theca are of course 

 characteristic of both genera ; besides this, a view of a com- 

 plete mesentery shows that a few synapticular brace together 

 the septa of this coral, and that between the synapticulse the 

 muscular pleatings of the mesogloea are gathered into strong 

 bundles in a very characteristic manner hitherto described only 

 in Fungia (fig. 5). The histological appearance of the cras- 

 pedon is also similar and characteristic in both forms. On 

 the whole, Stephanophyllia appears to bring Fungia into 

 closer relations with the Eupsammidse than have been gener- 

 ally allowed. At the same time it is to be remembered that 

 in Fungia the body wall is, at any rate partially, supported on 

 peripheral lamellar. 



The tentacles are ectocoelic as well as entoccelic, and are 

 covered with batteries of nematocysts. As has been pointed 

 out in other forms, the nematocysts are of two kinds, of which 

 the smaller alone are to be found in the tentacles. In the 

 craspedon, however, the larger kind is of exceptional dimen- 

 sions, measuring as much as *144 mm. by *012 mm. ; while 

 the smaller form is only •048 in length. A pair of directive 

 mesenteries occurred in the small fragment used for transverse 

 sections. 



