Zoology.-] NATURAL HISTORY OF VICTORIA. [Polyzoa. 



small avicularium, with a rounded mandible and serrated beak overlooking the 

 notch, and a conical rostrum posteriorly. Vicarious avicularia large, on the side of 

 thick calcareous elevations ; mandible large, broadly ligulate, and closing on strongly 

 serrated beaks. 



Reference. — Busk, Brit. Mus. Cat., Mar. Pol., pt. ii., p. 88, pi. cxix., ^g. 2, and 

 pi. cxx., fig. 6. 



Portland, Mr. Maplestone. 



The specimen figured forms a laminated mass, 1^ by 2 inches, 

 and is growing on a branch of a slender dark alga. 



Explanation of Figures. 



Plate 167. — Fig. 2, portion from the growing edge. Fig. 2a, more central portion, showing 

 also two large aricularia. 



Plate 16S. — Fig. 16, chitinous parts. 



Plate 167, Fig 3. 



CELLEPORA LIE AT A (McG.). 



Description. — Zoarium flat and adherent, or loosely adnate, or encircling stems 

 of algse or zoophytes, raised into usually regular sharp ridges, with deep furrows 

 between ; the extreme summits of the ridges forming* a sort of crimped edge. Zooecia 

 towards the summits of the ridges elongated ; mouth elongated, two spines (usually 

 absent) above, a rostrum on each side, one very large and produced into a long, 

 tapering process, and having towards its base an overhanging avicularium ; the other 

 rostrum (frequently absent) smaller, and usually with a similar avicularium; zooecia 

 in the furrows confused, nearly vertical, thicker, and having usually only one rostrum, 

 with an overhanging avicularium. 



Port Phillip Heads. 



This species is usually readily distinguished by the manner in 

 which the zooecia are disposed in sharp ridges, separated by deep 

 furrows. In some specimens, however, especially those not 

 encircling other objects, but flat and adherent or adnate, the ridges 

 are short, interrupted, not so high, and more resembling the eleva- 

 tions of C. mamillata. The extreme summits are produced into a 

 thin, frilled, sharp edge, as occurs in Densipora cornigata, to 

 which the mode of growth in many specimens is remarkably 

 similar. It is allied to C. albirostris. 



Explanation of Figures. 

 Plate 167. — Fig. 3, specimen, natural size. Fig. 3a, side view of the edge of one of the 

 ridges, magnified. Fig. 3ft, zooecia, from a furrow. 

 Plate 168. — Fig. 14, operculum. 



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