[Proc. Roy. Soc. Victoria, 21, (N.S.), Pt. I., 1908.J 



Art IV. — Farther Descriptions of the Tertiary 

 Polyzoa of Victoria. 



Part X. 



By C. M. MAPLESTONE. 



(With Plates VII., VIII.). 

 [Kead 9th April, 1908]. 



Crisia acuta, n. .sp. (PI. YTI., Fig. 1). 



Zoarium jointed, convex in front ; surface glabrous, with linear 

 punctations. Zooecia totally immersed and undefined. Thy- 

 rostomes 0.33 to 0.40 mm. apart, round ; peristome slightly 

 raised, with yery acute spinous process above. 



Locality, Cape Otway (J. Dennant). 



A single small specimen. This species is distinguished from 

 others by the convexity and smoothness of the front surface of 

 the zoarium, the undefined zooecia; the linear punctation, and 

 the very acute supra -oi-al process. 



Idmonea elongata, n. sp. (PI. VII., Fig. 2). 



Zoarium branching, 0.5 mm. broad. Zooecia in alternate 

 series of tliree, 1 to 2 mm. long. Distal ends turned outwards ; 

 distance between thyrostomes in each series 1 mm., but some 

 zooecia in the central portion are 2 mm. long. 



Locality, Mitchell River (J. Dennant). 



A robust species; it differs from all others in the very elon- 

 gated zooecia. 



Idmonea delicatissima. n. sp (Pi. VII., Fig. 3). 



Zoarium branching, very slender. Zooecia in alternate series 

 of two, ver}' narrow, 0.05 mm. wide, slightly rugose ; distal ends 

 exserted about 0.1 to 0.15 mm., exserted portion quite smooth. 

 Th}Tostomes 0.4 to 0.6 mm. apart. 



