114 



CEYLON PEARL OYSTER REPORT. 



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distinct sexes. They are placed beneath hydrothecse on the stems and branches, and 

 turn downwards at about the same angle that the hydrotheca? stand upwards. The 

 male gonotheca (Plate I., fig. 1) is cylindrical, with a wrinkled outline and rounded 



top, about ^ as long again as the hydrotheca ; while 

 the female (Plate L, fig. 1a) is truncated above, with 

 a marginal rim and a boss to one side of the upper 

 surface, and is broader and not so long as the first. 

 They both have the same coarse, granular texture as 

 the hydrotheca?. 



In a few specimens of about 2 inches in height, the 

 details of the zooid (text-fig. 1), its 34 tentacles, its 

 base resting on a floor above the base of the hydro- 

 theca, &c, are quite visible, and in these can be seen 

 distinct opercula with 4 valves (Plate I., fig. 1b). A 

 trace here and there of what may be broken portions 

 are the only indications of the operculum in the rest 

 of the material, which is composed of larger colonies 

 (text-figs. 2, 3), opaque and older looking in com- 

 parison with these small fresh bits. If the specimens 

 with opercula are not to be regarded as a different 

 species from those without, which I have not the 

 least inclination to believe, then the genus Thyro- 

 scyphus, Allman (3), founded for species having a 4-valved operculum, must either 

 be given up or the present species must be removed to that genus. I prefer the 

 former course ; and it seems probable that the opercula are only present in the young 

 condition and become lost in older colonies. 



For a Campanularian this is a remarkable species on account of its great size and 

 coarse habit, and its marked resemblance to a Sertularian (text-figs. 2, 3). It grows in 

 great profusion over some parts of the pearl banks, and is said to be characteristic 

 of the East Cheval Paar, where, in the Inspector's reports, the great masses sometimes 

 brought up by the divers are alluded to as " heather." Text-fig. 2 shows the species 

 in the fresh living state, and fig. 3 shows older coarser tufts, largely dead, such as 

 form the " heather " of the diver. 



Locality : Generally distributed round the coast of Ceylon, but especially large 

 and abundant on some parts of the pearl banks in the Gulf of Manaar. 



Campanularia corrugata, n. sp. Plate I., fig. 2. 



Trophosome. Stems of varying length rise from a creeping stolon, both being 

 thick and wrinkled, but without rings. Hydrothecae about yg of an inch in height 

 usually, but varying in size with age ; cylindrical, the same width all their length ; 

 transversely ringed more or less, sometimes with as many as 8 rings ; the aperture 



Fig. 1. Campanularia jwncea show- 

 ing expanded zooid, and hydro- 

 theca with operculum. Magnified. 



