Zoology/.'] NATURAL HISTORY OF VICTORIA. IPolyzoa. 



Port Phillip Heads, on algge and zoophytes. 



The branches of this elegant little species usually spring fi-om 

 dilatations of a slender creeping stolon very similar to that of 

 ^tea ; at other times, instead of dilatations, there are decumbent 

 zooecia connected by a creeping annulated tube, a branch rising 

 from below the aperture. They also sometimes arise directly 

 from the primary cell which is short, circular, and with a rounded 

 aperture occupying the whole of the contracted summit. The 

 zooecia are much elongated, attenuated below, each giving origin 

 by its summit to another connected by a short annulated tube. 

 The secondary branches are few and originate from the front of 

 the zooecia just below the aperture. When there are no branches 

 there is usually an aborted stem of a zoojcium. I have not seen 

 the ooecia, Mr. Hincks describes them as mitriform, somewhat 

 pointed above, with a keel down the centre, borne below the 

 aperture on an imperfectly developed cell. 



Explanation of Figdrbs. 



Plate 178. — ^Fig. 2, portion of a branch, magnified. Fig. 2a, portion of creeping stolon of 

 same. Fig. 3, portion of another specimen, seen from above. 



Plate 178, Figs. 4 and 5. 

 RHABDOZOUM WILSONI (Hincks). 



[Genus RHABDOZOUM (Hincks). (Sub-kingdom Mollusca. Class Polyzoa. Order 

 Infundibulata. Sub-order Cheilostoraata. Family Rhabdozoida;.) 



Gen. Char. — Zoarium phytoid, erect, consisting of celliferous, cylindrical, bifid or trifid 

 shoots, attached by numerous radical fibres springing from the sides ; straight hollow chitinous 

 rods springing from the sides of the primary shoots and supporting on their summits other 

 celliferous branches. Zooecia pyriform, with a consider.able oblique aperture, arranged in 

 longitudinal series round an imaginary axis. Avicularia sessile.] 



Description. — Zoarium consisting- of brandies supported on transparent, 

 hollow cbitinous rods, spring-ing from the sides of celliferous shoots attached by 

 bundles of radical fibres ; each rod spirally twisted, slightly at its commencement 

 and more strongly at its upper extremitj' where it is enlarged into a disc or sort of 

 calyx, surmounted bj' a circle of long, spreading and incurved glassy spines; each 

 calyx giving origin to a short branch which immediatel}' divides into usually three. 

 Zooecia pj'riform, slightly turned forwards above, each connected with the preceding 

 immediately behind its upper extremity, arranged in parallel longitudinal series 

 round the axis ; immediately below the aperture a transverse row of two or three 



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