1869.] DR. J. S. BOWRRBANK ON SILICEO-FIBROUS SPONGES. 329 
cule, closely resembling those figured by Bowerbank (‘ British 
Sponges,’ vol. i. figs. 190, 192).’’ I cannot agree with the learned 
Professor in this opinion. All the numerous specimens that I have 
seen, both separated from the sponge and in situ, have their natural 
basal terminations ; and no indication whatever exists of any central 
hexradiate spiculum from which they may have been separated. 
A few gemmules were observed adhering to the skeleton-fibres of 
the inner surface of the interstitial cavities of the sponge; they are 
similar in character to those of I. panicea, but in the specimen under 
consideration they are not nearly so numerous as in the Porto-Rico 
specimen of that species. 
IPHITEON SUBGLOBOSA, Bowerbank. 
F Dactylocalyx subglobosa, Gray, P. Z.S. 1867, p. 506, plate xxvii. 
e@. 1: 
Sponge massive, somewhat cyathiform, sessile. Surface uneven. 
Oscula and pores unknown. Dermal membrane—retentive spicula 
spiculated biternate, minute, very numerous? Skeleton symmetri- 
cally radial; areas confluent, somewhat irregular, mostly six-sided, 
spaces within triangular; skeleton-fibre at the external surface 
coarsely and irregularly tuberculated ; fibre within the sponge mi- 
nutely tuberculated ; disposition of the tubercles sublinear. Auxi- 
liary fibres rectangulated hexradiate, abundantly spinous ; radii spi- 
nulate. External defensive spicula fusiformi-acerate, very large and 
long, distal terminations occasionally incipiently spinous. Intersti- 
tial spicula rectangulated hexradiate, very slender, radii subclavate, 
basal ray very long. Spicula of the membranes—retentive spicula 
spinulo-quadrifurcate and pentafurcate hexradiate stellate, numerous; 
margins of the spinulate terminations crenulate. 
Colour in the living state unknown. 
Hab. Malacca? (Dr. J. EB. Gray). 
Examined in the state of skeleton. 
This sponge is in the collection at the British Museum. It is 
figured of the natural size in the ‘ Proceedings’ of this Society for 
1867, plate 27. fig. 1; and at p. 506 of the same volume, Dr. J. KE. 
Gray gives the following brief description of it :—“ Sponge subglo- 
bose, with a deep central concavity above; the outer surface with 
irregular anastomosing oscules. 
‘“‘ Hab. Malacca?” 
The sponge is based on a fragment of coral, and has very much 
the form of a young and undeveloped specimen of one of the best 
description of Turkey sponges, in which the form of the cup is rather 
indicated than produced ; and it is very probable that in its fully 
developed state it will be found to be a truly cyathiform species. 
The expansile dermal system of the sponge has been entirely de- 
stroyed; the oscula and pores are therefore unknown to us; but on 
one fragment of the outer portion of the skeleton submitted to exa- 
mination there was a very small piece of the dermal membrane ad- 
hering to the surface of the skeleton, and this was densely crowded 
