MARINE MISCELLANEA. 225 
Wo 
whether the erect fascicle of elongate siliceous spicula encrusted by the polyp was 
the product of this organism, or an integral part of the subspherical sponge body, 
usually, but not invariably—it first falling to decay—found seated at its apex, was the 
subject of a prolonged and most heated controversy in the earlier days of biological 
investigation. The names of Dr. J. E. Gray and Dr. Bowerbank will be remembered by 
all contemporary zoologists as the doughty champions of these respective interpretations. 
The Zoantharian discovered and described by the author also possesses the 
somewhat unusual distinction of an erect supporting fulcrum. The fulcrum in this 
instance is, however, altogether different in character to that of the commensal Palythoa. 
In place of a relatively solid axis, Acrozoanthus australie is built up on a hollow 
or tubular support of parchment-like consistence, which, when denuded of the 
encrusting polyps, exhibits a singularly symmetrical zigzag growth plan. Its angular 
projections are, moreover, usually developed on the same plane. The polyps in the 
living organism invest this structure completely with their united flesh or czenosarc, 
but project in the most conspicuous clusters from the alternating prominences of the 
tubular support. As figured and described in the author’s original account of this 
organism, the individual polyps are attractively coloured, the semi-contracted zooids 
more particularly presenting a rounded button-like contour, in which the tints of bright 
emerald green and red-brown specklings are predominant. When fully expanded, the 
brighter green hues of the column and sphinctral regions are concealed by the radiating, 
red-brown tentacles. 
Acrozoanthus was first collected by the writer on the foreshore at Port Darwin, 
subsequently at Cambridge Gulf, Torres Straits, along the Great Barrier Reef, and 
finally at Roebuck Bay in Western Australia. It is thus shown to be indigenous to 
all quarters of the tropical Australian sea-board, and is in that respect a fitting claimant 
to its allocated specific title. With the exception of the gatherings made in Western 
Australia, the examples observed or obtained on the north and eastern Australian coasts, 
and from which the original description was drawn up, were growing in isolated colony- 
stocks only, or, at the most, in groups of two or three contiguous polyparies on the 
foreshore or in the reef pools of the districts named. The abundance, however, in 
which the polyp-denuded tubes were found among the flotsam and jetsam cast upon 
the beaches testified to its growing in considerable abundance in some less accessible 
and probably deeper area of the sea bottom. 
The writer’s later quest for this interesting type on the coasts of Western 
Australia was rewarded by its discovery in the neighbourhood of Gantheaume Point, 
FF 
