62 Rew D7. Hincks’s Contributions towards a 
Rhabdozoum Wilsont,n. sp. (Pl. VIII. fig. 4.) 
Zoartum composed of a number of shoots, held together by 
a rather thick compound stem made up of the radical fibres 
emitted from the base of each shoot, and forming a much rami- 
fied, spreading, arborescent structure ; each shoot composed 
of two parts—(i) a short bi- or trifurcate cylindrical stem, 
bearing celis, from which the radical fibres originate, and (11) 
a number of erect, slender, chitinous rods rising from this 
stem, supporting on their summit other celliferous stems of 
similar structure, dichotomously branched, the branches 
widening upwards; rods transparent, terminating above in 
a cup-like expansion, the edge of which is closely set round 
with spines, distinctly annulated immediately below the cup. 
Zoecia subpyritorm, disposed in longitudinal series, and so 
that the orifices range in oblique transverse lines across the 
stem, translucent, surface smooth and glossy; aperture oval, 
occupying about one third of the length of the cell, with 
a thin margin, somewhat contracted below, the lower extremity 
turned slightly inwards, inferior portion of the cell narrowing 
downwards ; immediately below the aperture two or three 
extremely long curved spines, articulated to a short tubular 
base, replaced in many of the cells by a small aviculartwm on 
a mound-like elevation, with a pointed mandible directed fo1- 
ward. Occium terminal, rounded, smooth. Height of the 
largest specimen about 14 inch. 
Loc. Off Port Phillip Heads, Victoria (Mr. J. Bracebridge 
Wilson). 
The appearance of this very curious species is quite unique. 
At first sight, a well-developed composite specimen is not 
unlike a mass of one of the larger Australian Bicellarie ; but 
the resemblance is merely superficial. The tall and slender. 
pedicels, crowned by the delicate feathery tufts, are unlike 
any thing which I have hitherto met with among the Polyzoa, 
unless they may be compared with the stem of such a form as 
Kinetoskias (Naresia) cyathus, Wyville Thomson, which 
Busk regards as representing a radical tube, or rather “a. 
coalesced bundle of tubes” *. 
The basal or primary portion of the shoots in R. Wilson 
is usually composed of a triplet of short stems, which converge 
below, and are borne on akind of peduncle made up of numerous 
radical fibres compactly bound together, which ultimately 
unite with other peduncles, all of them, towards the base of 
the specimen, forming a thick trunk. ‘The tibrous peduncle: 
* “Ona peculiar Form of Polyzoa closely allied to Bugula (Ainetoskias; 
Kor. & Dan.),” Micr. Journ. vol. xxi. n. s. 
