Zoology.'] NATURAL HISTORY OF VICTORIA. \_Pohjzoa. 



Port Phillip Heads, a single specimen, Mr. J. B. Wilson, 

 I have some doubt whether to refer this species to Cellepora or 

 Schizoporella. The marginal zooecia are quite horizontal, those 

 further removed confused, but not so erect as usual in Cellepora. 

 The sub-oral rostrum seems to be unarmed, but it is possible that 

 there may be an avicularium on its internal surface. I have 

 another specimen which seems to belong to the same species. 

 In it the zooecia are shorter, some smooth, but others Avith glassy 

 elevations, the sub-oral process rises and curves forward, or 

 occasionally inclines to one side, and has a small avicularium on 

 the inner surface towards the summit. The ooecia are rounded, 

 with a small, nearly circular area, punctate within the margin. 

 There are also several vicarious avicularia with spatulate 

 mandibles. This latter specimen agrees with Busk's C. signata 

 of the " Challenger " Polyzoa in the markings of the ooecia and 

 the vicarious spatulate avicularia, but differs in the sub-oral mucro 

 and in the wider and shallower sinus. 



Explanation or Figure. 

 Plate 148. — Fig. 9, portion of specimen, magnified. 



Plate 148, Fig. 10. 

 CELLEPORA TIARA (McG.). 



Description. — Zoarium minute, encrusting-. Zooecia small, rather short, 

 smooth, confused; primary mouth with a rather deep, narrow, slit-like sinus; 

 peristome considerahly developed, with a stout, thick mucro at one side, usually 

 slightly overarching- the mouth, and surmounted by a comparatively larg-e 

 avicularium with broadly triangular mandible. Ocecia sub-globular, reclinate, 

 with a sub-triang-ular, smooth, or sculptured area. 



Port Phillip Heads. 



The few specimens I have are all growing on Retepora 

 monilifera. It is distinguished by the thick, incurving oral 

 mucro and the character of the area on the front of the ooecium. 



Explanation of Figures. 

 Plate 118. — Fig. 10, specimen, natural size, encrusting Kctepore. Fig. lOra, portion of 

 ame, magnified. In all the zooecia the primary mouth is obscured by the peristome. 



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