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PACIFIC SCIENCE, Vol. Ill, April, 1949 
following) properly reduces them to synonyms. 
There is a species well-named sacciformis ( Ant- 
arctic). Another ( kilakaria ) from India is 
like nucula except that it is bright orange in 
color. Hentschel’s jinensis is like australiensis, 
but with huge spicules. Thus euastra would 
appear to be the sixth valid species of the genus. 
It is set off by its lack of spherasters — in fact 
it has exceedingly few spicules of any kind 
and thus approaches the genus Chondrosia, 
which it also resembles in color. In many other 
respects Chondrosia and Chondrilla are the 
same, the two genera being closely related. 
Xestospongia exigua (Kirkpatrick) 
This third species of sponge, collected in Yap 
by Dr. Hiatt, is here identified with some hesi- 
tation, and therefore is accompanied by a con- 
densed description of the specimen. It was 20 
to 30 cm. long, clavate, with contained living 
bivalve mollusks at intervals. It grew on tidal 
flats in the harbor at Yap. Only a fragment has 
been preserved. When dry it is very dark gray; 
when alive nearly black. It is hard but crumbles 
easily. It has a fairly even surface with oscules 
2 mm. in diameter and about 2 cm. apart; the 
pores are very abundant and about 100 g in 
diameter in the dried specimen. The spicules 
are packed densely around gross chambers, thus 
approximating a reticulate structure; they are 
oxeas 6 by 135 to 6 by 150 g. A few much 
thinner ones are probably juvenile. 
Kirkpatrick (1900: 139) described Petrosia 
exigua from the East Indies and de Laubenfels 
’(1936: 70) transferred it to Xestospongia. On 
the basis of the original rather brief description 
the only difference from the Yap specimen 
seems to be that the original had hollow ascend- 
ing tracts. If it were better known, further 
differences might be revealed, demanding a 
different, perhaps new, name for the Yap 
species. The latter is represented by U.S.N.M. 
catalogue number 22733. 
REFERENCES 
Burton, M. 1924. The genus Chondrilla. 
Ann. and Mag. Nat. Hist. IX, 14: 206-209. 
Carter , 1 H. J. 1873. On two new species of 
Gummineae, with special and general obser- 
vation. Ann. and Mag. Nat. Hist. IV, 12: 17— 
31, pi. 1. 
de Laubenfels, M. W. 1936. A discussion of 
the sponge fauna of the Dry Tortugas in par- 
ticular, and the West Indies in general, with 
material for a revision of the families and 
orders of the Porifera. Carnegie Inst. Wash., 
Pub. A6l. 225 pp., 22 pis. 
Kirkpatrick, R. 1900. On the sponges of 
Christmas Island. Zool. Soc. London, Proc. 
1900: 127-141, 2 pis. 
Schmidt, E. O. 1862. Die Spongien des Adri- 
astischen Meeres. viii-f 88 pp., 7 pis. Leipzig. 
Topsent, E. 1896. Materiaux pour servir a 
letude de la Faune des Spongiaires de France. 
Soc. Zool. Prance, Mem. 9: 113-133. 
Wilson, H. V. 1925. Siliceous and horny 
sponges collected by the U. S. Fisheries 
Steamer ’'Albatross” during the Philippine 
Expedition, 1907-10. U. S. Natl. Mus., Bui. 
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