54 
Genus Sarcophytum. 
i. Sarcophytum acutangulum (Marenzeller). (Plate XVI, Fig. 6; Plate XXVII, Fig. 4). 
For descriptions see: 
KUKENTHAL, Fauna Siidwest-Australiens, Bd. Ill, 1910, p, 25. 
Marenzeller, Zool. Jahrb. vol. 1, 1886, p. 357. 
PRATT, Ceylon Pearl Oyster Report Roy. Soc. London, 1905, XIX, p. 251, (as X. contortum). 
Stat. 133. Lirung, Salibabu-island. Up to 26 M. Mud and hard sand. 1 Ex. 
Stat. 142. Laiwui, Obi Major. Reef. 3 Ex. 
Stat. 213. Saleyer. Reef. 1 Ex. 
Stat. 240. Banda. Reef. 3 Ex. 
Stat. 299. io° 52'.4 S., i23°i / .iE. 34 M. 3 Ex. 
Stat. 301. io°38 / S., 123 0 25 / .2 E. 27 — 45 M. Mud, coral and Lithothamnion. 1 Ex. 
A characteristic folded colony, from Station 240, with about a dozen main folds on the 
disc, and with secondary folds on these, so that the contour of a main fold sometimes suggests 
an oak leaf. The height is 8.5 cm., the maximum diameter of the disc is 7 cm., and the diameter 
at right angles to this is 5.4 cm. The base of the stalk has a diameter of 3.5 cm., and the 
distance from the base to the margin of the disc is about 8 cm. The disc is not spread out 
beyond the stalk in mushroom-like fashion. 
As Marenzeller notes, the siphonozooids are rather indistinct. The texture of the surface 
is gritty. The spicules agree entirely with those figured by Marenzeller, but there seems to 
us to be a greater number of the very narrow, delicate spindle-types with relatively few thorns. 
The typical adult form of this species is much folded, see Miss Pratt’s figure of S. con- 
tor him and Kukenthal’s photograph of V. acutanguhim in which he included Miss Pratt's species. 
But it is of considerable interest that the Siboga collection shows a number of growth-stages 
which lead from a simple mushroom-like type to the much plaited adult. As regards shape these 
young forms seem very different, but they agree inseparably as regards spicules, siphonozoids, 
and texture. Illustrations of the series have been figured, and the case is of so much interest 
that we have given details of a number of the gradations (Plate XXVII, fig. 4). 
Of two colonies from Station 240, the smaller colony, like a button mushroom, 1.8 cm. 
in height, has a round capitulum with a maximum diameter of 1.2 cm., the stalk having a main 
diameter of 0.4 cm. The larger has a height of 2.5 cm. and a capitulum with diameters of 
approximately 1.7 and 1.1 cm. The margin of the capitulum is slightly lobate, as if showing 
the beginning of folding. In both, the autozooids evenly cover the whole surface about 1 mm. 
apart, and between them lies a single row of siphonozooids. The colour is a creamy grey. 
The spicules show the following forms: 
[a) strong, mostly straight spindles covered with compound or simple warts which in some tend 
to lie in whorls; up to 0.4mm. in length and 0.07mm. in breadth; 
<p) more slender spindles, up to 0.4 mm. in length with a breadth of 0.02 mm., with fewer and 
more simple prominences ; 
(c) short clubs with broad heads covered with either blunt compound warts, some at right angles 
to the axis, or with sharp more upwardly projecting processes. A common length is 0.13 mm. 
with a breadth across the head of 0.05 mm. 
