16 Records of the Indian Museum. [VoL. XI, 
Although this large and conspicuous sponge has been known, 
so far as its external form is concerned, for nearly a century, its 
true systematic position has only been discovered, by Vosmaer 
and Topsent, in the last few years. There is a fine series of dried 
specimens from Singapore, the original locality, in the Indian 
Museum; but they do not include the type. The species seems to 
me to be very closely related to Cliona celata, from which it differs 
in its stouter spicules but which it resembles in its general struc- 
ture and in particular in that of the papillae. So far as these are 
concerned it agrees more closely with C. celata than with C. vim- 
dis, of which Vosmaer was apparently prepared to regard it as a 
variety. 
Some of our specimens contain at the base both Jamelli- 
branch and Gastropod shells, as well as many small pebbles. The 
latter, being of hard stone, are intact, as are also some of the 
shells. Others, however, both of bivalves and of Gastropods, have 
had ramifying grooves excavated on their surface by the sponge. 
In one Lamellibranch shell that was partially embedded in it 
the grooves are entirely confined to the embedded position. At 
least one Gastropod shell, which was extracted from the centre of 
the basal portion of a large specimen, is wholly permeated and 
nearly destroyed by excavations filled with sponge substance. I 
am convinced by these facts that the excavations in shells found 
in large specimens of C. fatera are of a secondary nature, and it 
seems improbable, in any case, that so large a sponge, if it com- 
menced life in the thickness of any Molluscan shell, should not 
have completely destroyed that shell before reaching its full size. 
So far as I am aware, C. pfatera has as yet been found only 
in the neighbourhood of Singapore and Java, where it is abundant. 
If it occurred in the Gulf of Manaar, where several large collec- 
tions of sponges have been made, so conspicuous an object could 
hardly have escaped notice. Indeed, its place seems to be taken 
in the seas round Ceylon and India by the Halichondrine sponge 
Petrosia testudinaria (amarck), which bears a considerable super- 
ficial resemblance to it, although the ‘‘ cup’’ and the “‘stalk”’ 
are not so clearly differentiated. 
Genus Thoosa, Hancock. 
1849. Thoosa, Hancock, Ann. Mag. Nat. Hist. (2) Il, 
Pp. 345- 
1887. ms Topsent, Arch. Zool. expérim. (2) V’, p. 88. 
1891. ad., ibid., (2) IX, p. 577. 
1905. ? Cliothosa, ie, Bul. Mus. Hist. Nat. Paris, XI, p. 95. 
This genus is much less well known than Cliona. Most of the 
species, being of tropical origin and having a very inconspicuous 
appearance externally, have been described from dried specimens 
extracted from shells or corals, and many of these have been im- 
perfect. Possibly it will ultimately be proved that several quite 
