A JIONOGRAPH OF THE TERTIARY POLYZOA OF VICTORIA. 71 



punctured, but without special pores ; thyrostome rouiuled al)ove, without special 

 development of the peristome. Ocecia external. 



Lepralia, Johnston. 



Zocecia usvially closely united to each other ; thyrostome semicircular or horse- 

 shoe-shaped, usually slightly contracted at the sides ; the lower margin straight, or 

 slightly hollowed, or convex upwards, generally a small, sharp denticle on each side 

 at or above the angle. 



1. L. ahdita, u.sp. PI. X., fig. 1. 



Zoarium encrusting. Zoa'cia quadrate or oJDScurely hexagonal, nearly flat, with 

 a row of small, deep areolae along the distinct raised margins ; thyrostome A\ade, 

 straight below, with a small denticle at each angle. Ocecia round, prominent, at 

 the base of the zooecia, without external opening. 



S.P. 



The ocecia are very peculiar, being situated at the base of the zocecia above the 

 raised lower margin, and having no external opening. The zocecium below has no 

 thyrostome. It is, however, possible that the closure of these zocecia may be 

 abnormal, and that other specimens may shew the usual structure. In Cellepora 

 abdita the ocecia have a similar structure. 



2. L. qtiadmta, McG. PI. X., figs. 2, 3. 



Esehani quadrata, McG., P.Z.V., 48; Leprcdia, id., C.V. 



Zoarium erect, foliaceous, uni- or bilaminate. Zooecia usually in linear series, 

 elongated, quadrate, slightly convex or nearly flat, with numerous rounded pits or 

 pores ; thyrostome rounded above, contracted below, the lower lip arched upwards, 

 a sharp denticle at each angle ; avicularia short, broadly spatulate, very rare in the 

 fossils. Ocecia large, perforated. 



M.C. ; B. Living. Australia. 



Most of the fossil specimens are unilaminate, but they are of small size, and I 

 believe this condition is owing to the splitting of the layers. The zocecia in recent 

 specimens are separated by raised margins, absent, however, in almost all the fossils. 

 The distinctness of the pits or pores varies. The avicularia seem to be very rare in 

 the fossils, the only one I have seen being that shewn in fig. 3. In recent specimens 

 they are frequently found on each side of a thyrostome below an ocecium. The 

 ocecia are porous or pitted like the zooecia, and may be traversed by raised lines. 

 The oral denticles are not always visible even in recent specimens. 



