88 PERCY SLADEN TRUST EXPEDITION 



Polyps. (1) Exocoelic tentacles absent. (2) Stomodgeal ridges thicker than broad, 

 their sides sloping away from apices to bases. (3) About seven principal couples of 

 mesenteries present. (4) In the stomodeeal region of polyp subsidiary couples of 

 mesenteries about twice the number of principal couples. (5) In the same region, 

 entocoelic pleats narrow, thick, undivided, unconstricted at their bases, directed obliquely 

 towards stomodseum, not extending beyond outer two-thirds of width of principal 

 mesenteries, better seen in their outer halves. (6) Mesenterial endoderm thin in pleatal 

 region, but gradually swelling towards stomodaeum. (7) Convolutions of mesenteries 

 abundant below stomodasum to base of polyp, massed together in intermesenteric 

 chambers. 



Remarks. A. Polyps. These are smaller than in F. doreyensis but more 

 regular in form — either circular" or oval. Owing to close approximation of corallites 

 there is little or no coenosarc. An appearance of binary fission frequently results 

 fi'om the presence of two oral openings placed at equal distances from the tentacular 

 ring. In the two polyps examined 7 principal couples of mesenteries are present, 

 2 of them being incomplete, and 13 subsidiary couples. The convolutions of the 

 mesenteries are scarce in the stomodseal region. The entocoelic tentacles equal the 

 entocoeles in number. In the large bluntly pointed terminal batteries long narrow 

 pink bodies are found as in the previous species ; certain appearances suggest that these 

 may be immature stages in the development of nematocysts II h. About six sub-terminal 

 batteries are present. 



The stomodeeum is almost circular in transverse section, its diameter being 1'5 mm., 

 its ridges are much less broad than in F. doreyensis, appearing more or less conical, with 

 no deep grooves between, their mesoglaea only slightly thickened. Both ectoderm and 

 endoderm are vacuolated as in the previous species, but the tentacular endoderm is 

 thinner. Nematocysts II are present in the coils of the filaments in addition to those 

 of types I and III. In the mesenteries the mesogleea is usually thinner in the non-pleatal 

 than in the pleatal region, but is thickened to a short distance from the stomodseal 

 attachment ; on this thickened region narrow entocoelic pleats are seen. Below the 

 stomodseal region of the polyp the entocoelic pleats extend over the entire width of 

 the principal mesenteries. 



Both the polyps sectioned had eggs in every mesentery, in one or two longitudinal 

 rows. Immature germ cells, surrounding the eggs, are better seen than in the polyps of 

 the previous species. The proliferation of the calicoblastic ectoderm is conspicuous even 

 towards the bases of the polyps containing cell elements similar to those of the immature 

 ova. This appearance suggests that these polyps were in a state of reproductive activity. 

 When all the eggs have been formed, as in the polyps of F. doreyensis, the calicoblast 

 loses all signs of its proliferating activity and the follicle-cells become fewer. 



In the Berlin Museum is a specimen (No. 739) measuring 14x12x7 cm. referred 

 to Favia rotidosa by Ehrenberg (PL 35, fig. 1), resembling Gardiner's example no. 1 

 (p. 770, fig. 19). 



Number of polyps examined, two, from a specimen from Hulule, Maldives. 



Localities. Maldives: Hulule (5) ; Goidu (l). Ceylon (2). Kotuma (1). Funafuti 



