218 CEYLON PEARL OYSTER REPORT. 



Australia and New Zealand, but his identifications are not always trustworthy, and 

 he appears to me to have got a wrong conception of the species. Thus he states that 

 " in every case the sponge is attached by a short peduncle." He also includes (perhaps 

 rightly) the cup-shaped Phyllospongia holdsworthi in the species. 

 R.N. 104a (Gulf of Manaar). 



Phyllospongia holdsworthi (Bowerbank). 



1873, Spongionella holdsworthii, Bowerbank (8); 1889, Phyllospongia papyracea, pars, 

 Lendenfeld (66). 



There are several exquisitely cup-shaped specimens of this sponge in the collection. 

 Bowerbank's figures and descriptions do not appear to me to be very typical, and it 

 seems not impossible that he had also before him, when writing, specimens of 

 Phyllospongia papyracea. The specimens which I have examined are regularly cup- 



Fig. 5. Phyllospongia holdsworthi, half nat. size. 



shaped (see text-fig. 5), with an entire margin and a very well developed peduncle 

 branching out into root-like processes below. The wall of the cup is only about 

 1*5 millims. thick, stiff and tough and slightly flexible in the perfectly dry state. 

 Both surfaces are smooth or nearly so, but show feebly developed concentric and 

 sometimes radiating ridges. The vents are minute, usually circular in outline, and 

 abundantly scattered over the inner surface only of the cup, which is covered by a 

 thin sand-cortex not sufficiently developed to conceal the minutely reticulate character 

 of the dermal skeleton. There is no sand-cortex on the outer surface, which is also 

 minutely reticulate. Professor Herdman informs me that the colour of the sponge 

 in life is purplish-brown, and my dry specimens still retain a distinctly jjurple tinge 

 in places. 



The skeleton is a close-meshed but very irregular network of horny fibre, mostly 

 about 0*02 millim. in diameter and free from sand, but with stouter primary lines 

 radiating to the surface and containing numerous comparatively large sand-grains, 

 especially towards the inner surface of the sponge. 



