A MONOGRAPH OF THE TERTIARY POLYZOA OF VICTORIA. 35 



3. M. striata, n.sp. PI. IV., figs. 9, 10. 



Zoarium unilaniinate, probably encrusting or adnate. Zooecia very large, 

 rounded or ovate, united in front, closely connected behind by very short calcareous 

 tubes ; aperture occupying the whole area, ovate, with a thickened, concentrically 

 striated margin, which is raised at the distal end, where it is slightly incurved and 

 smooth externally. Avicularia between the zooecia, small. 



S.P.; M.C. 



Var. orbicularis. Zooecia large, nearly orbicular, the margin more prominent, 

 smooth and not specially raised at any part. Avicularia numerous, situated 

 between the margins. 



S.P. 



In this very marked species the zooecia are very large and deep, united at their 

 margins in front. Posteriorly they are convex, closely connected by calcareous 

 tubes, which are so short as to be in many instances indistinguishable. It is allied 

 to M. radicifera in the tubular connection of the zooecia. Prom the presence in 

 some specimens of minute pores on the posterior surface, it is probable that it has 

 been attached by small radical tubes. The variety orbicularis ought perhaps to be 

 separated as a distinct species, distinguished by the rounded form of the zooecia and 

 the absence of the raised, smooth, inturned portion of the margin found in the 

 normal form. In some specimens, however, there are indications of this structure. 



4 M. marginata, n.sp. PL IV., fig. 11. 



Zoarium bilaminate, dividing into narrow flat branches. Zooecia large, 

 alternate in longtitudinal series, elongated with rounded angles, separated by raised 

 margins ; a smooth lamina sloping inwards ; aperture elliptical, occupying about 

 two-thirds of the area, with a distinct thickened margin. 



S.P.; M. 



On the margins are a few obscure markings, which may possibly indicate the 

 attachment of lateral spines. It is characterised by the smooth, highly calcified 

 lamina and the very distinct rim round the aperture. 



5. M. elliptica, n.sp. PI. IV., fig. 12. 



Zooecia elongated, continuous and indistinct longitudinally ; area elliptical, 

 occupying the whole of the front except a small portion below, with thickened, 

 smooth or very minutely crenulated margins. 



S.P.; M.C. 



P2 



