Sponges of Palau, I — BERGQUIST 
183 
Spirastrella aurivilli Lindgren, 1897, p. 484. 
Spirastrella aurivilli Lindgren, 1898, p. 322, 
pi. 17, fig. 11, pi. 18, fig. 4. 
Spirastrella aurivilli Vosmaer, 1911, p. 21, 
pi. 19, fig. 22a-c. 
Spirastrella aurivilli Burton, 1934, p. 571. 
Cliona aurivilli de Laubenfels, 1936, p. 154. 
occurrence: Sta. 92 A, 258. 
DESCRIPTION: The specimen from Sta. 92 is 
damaged, the other is entire and in good condi- 
tion. It fills a cavity, 9.5 X 7.5 X 16 cm, inside 
coral limestone; 0.5-1. 5 cm of coral remains 
surrounding the central sponge mass. The 
sponge produces numerous hollow papillae 
with slightly expanded flattened tips. These run 
to the surface through straight channels obvi- 
ously bored by the sponge. They range from 
0.8-12 mm in internal diameter, up to 18 mm 
in external diameter, and extend up to 3.5 cm 
above the surface of the rock. A great number 
of papillae are flush with the surface of the 
rock or project only 1-2 mm from the chan- 
nels; these always have a single opening. Many 
of the larger papillae are irregular and bear 
2-3, rarely 6 openings, each terminal upon a 
stout branch of the axial papilla. 
COLOR: In alcohol, dull pinkish-red (R 5/2). 
TEXTURE: The central mass is soft and rub- 
bery; the papillae are hard, stiff, and relatively 
brittle. 
SURFACE: The external surface of the papil- 
lae is finely hispid and lumpy, reminiscent of 
many massive species of Spirastrella. The termi- 
nal region of the papillae is usually markedly 
irregular, suggesting that contortion is a tem- 
porary condition resulting from contraction of 
all external openings. 
SKELETON: Lindgren’s (1898) description of 
the disposition of the skeleton in S. aurivilli 
forma excavans applies with slight alteration to 
this specimen. In Lindgren’s specimen the spi- 
rasters were not only absent from the papillae 
but were rare in the interior of the sponge; 
the large tylostyles were also rare. 
In the specimen from Sta. 92 the spiras- 
ters are extremely abundant in the base; large 
tylostyles are abundant throughout both speci- 
Fig. 2%a. Spirastrella aurivilli Lindgren. Sta. 258. 
