Zoology.-] NATURAL HISTORY OF VICTORIA. iPolyzoa. 



Plate 167, Fig. 1. 

 CELLEPORA ALBIROSTRIS (Smitt). 



Description. — Zoarium encrusting', or adnate, or partly free, of a white or 

 greyish-brown colour. Marginal zooecia horizontal^ ovate, distinct, smooth ; mouth 

 lofty, arched above, straight below ; at first plain, but subsequently a transverse 

 process originating from one side below the mouth, carrying a small avicularium at 

 its inner end, external to which it gives rise to a conical spine which is at first short, 

 but with growth attaining a considerable height, and frequently with the adjacent 

 part of the zooecium enlarged ; older zooecia more erect and confused, but with the 

 same structure. Ooecia sub-globose. Vicarious avicularia on calcareous elevations, 

 with large, broadly ligulate mandibles closing on serrated beaks. 



References. — Discopora albirostris, Smitt, Floridan Bryozoa, pt. ii., p. 70, 

 pi. xii., figs. 234-239 = Gellepora albirostris, Busk, Challenger Polyzoa, pt. i., 

 p. 193, pi. xxxiv., fig. 7, and pi. xxxv., fig. 3. 



Port Phillip Heads. 



I have considerable doubt whether this is identical with Smitt's 

 and Busk's species. All my specimens are encrusting or fixed to 

 roots of LaminaricB. None of them show the two long, slender, 

 rigid, oral spines figured by Smitt and Busk, but the former 

 remarks that they are sometimes wanting. The pre-oral rostra 

 are also thicker. The opercula are usually, as mentioned by these 

 authors, of a dark colour, and contrast strongly with that of the 

 zoarium. The shape, however, differs from Busk's figures. 



Explanation op Figures. 



Plate 167. — Fig. 1, specimen, natural size. Fig. la, zooecia, from the growing margin, 

 magnified. Fig, \b, two zooecia and small vicarious avicularium. Fig. Ic, vicarious avicu- 

 larium, mouth of zocecium, and several pre-oral rostra from others. Fig. Id, zooecia and 

 ooecium, from central part. 



Plate 168. — Fig. 12, operculum. 



Plate 167, Fig 2. 

 CELLEPORA FUSCA (Busk). 



Description. — Zoarium, very much lobed, the lobe bilaminate, narrowed at the 

 base and wider above. Marginal zooecia ovate, distinct, smooth; primary mouth 

 entire, but becoming notched fi:om the growth of a transverse process having a 



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