Zoology.-} NATURAL HISTORY OF VICTORIA. \Polyzoa. 



Readily distinguished from all other species by the large circular 

 opening on each side of the cells. 



On algae, frequent at Queenscliff and other places. 



Explanation op Figures. 



Plate 25. — Fig. 2, specimen, natural size. Fig. 2a, same, highly magnified, showing the 

 irregular form of the cells, the two sharp spines and several of the ovicells on the upper part of 

 the figure, and the triangular avicularia on some of the cells. 



Plate 25, Fig. 3. 



MEMBEANIPORA CILIATA (P. MacGil.). 



Description. — Cells oval; front almost entirely occupied by a calcareous 

 granular membrane. A series of (4-7) long hollow spines articulated round the 

 upper end of the cell. 



Reference. — P. MacGillivray, Trans. Roy. Soc. Vict., 1868. 



It is at once distinguished by the series of long, thick, hollow, 

 articulated spines, which are so large as to be distinctly visible 

 without a lens, and frequently obscure the whole front of the cell. 

 In the figure the cells are rather too prominent and the spines too 

 small. 



Occurs frequently in small patches on algae at Queenscliff and 

 Williamstown. 



Explanation of Figuhes. 



Plate 25.— Fig. 3, specimen, natural size. Fig. 3a, same, highly magnified, showing the 

 numerous long spines to aperture. 



Plate 25, Fig. 4. 



MEMBRANIPORA MAMILLAEIS (P. MacGil.). 



Description. — Cells oblong, arranged in longitudinal series, alternate; front 

 entirely occupied by a thick membrane; mouth with a hollow, blunt spine on 

 either side. Avicularium large, situated at the base of a cell, mandible triangular, 

 much elongated, directed obliquely upwards. 



Reference. — P. MacGillivray, Trans. Phil. Instit. Vict., v. iv., p. 165, 1860. 



It may readily be distinguished by the uniformity of size and 

 alternate arrangement of the cells and by the size and obliquity of 

 the avicularia. 



[30] 



