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



cells are tlie same, and they are separated by prominent raised 

 lines. The difference consists in the presence of a suboral avicu- 

 larium in L. subimmersa, which may not be constant, and the 

 different elevation of the ovicell. In L. subimmersa it is large, 

 closely incorporated with the cell above, from the surface of which 

 it is slightly raised, while in L. anceps it is very prominent, the free 

 margins projecting over the edges of the cells on each side. 



Explanation of Figures. 



Plate 35.— Fig. 6, specimen, natural size. Fig. 6a, portion, magnified. Fig. 66, small portion, 

 more highly magnified, to show ovicell and mouth. 



Plate 35, Fig. 7. 



LEPRALIA MAPLESTONEI (P. McG.). 



Description. — Cells ovate, surface perforated; mouth arched above, straight 

 below, with a central, rounded notch, unarmed or with two or three short spines. 

 Ovicell round, with numerous large perforations in the central part, the circumference 

 being occupied by a smooth, thickened rim. 



Williamstown, Mr. Maplestone. 



In the only two small specimens I have seen, the surface is so 

 much obscured by the ovicells that it is difficult to distinguish the 

 real shape of the cells. The ovicells are very peculiar ; they are 

 round, and the circumference is occupied by a thickened band 

 which extends down each side of the mouth, terminating by forming 

 an arched process projecting over in front of the lower lip and 

 nearly meeting in the centre. A row of large perforations surrounds 

 the ovicell immediately within the thickened rim, and there are 

 other smaller ones in the central space. 



Explanation of Figures. 



Plate 35. — Fig. 7, specimen, natural size. Fig. 7a, portion, magnified. Fig. 7b } small portion, 

 more highly magnified. 



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