Tertiary Polyzoa of Victoria. 23 



Tpigonopopa, nov. gen. 



Zooecia elongated, quadrate. Thyrostome inversely subtri- 

 angular, curved distally, with a raucro in the proximal angle. 

 Sides with a macro at the distal ends, forming a small, circular 

 channel or opening on each side. 



The leading characteristic of this genus is the form of the 

 thyrostome. 



Trigonopopa vermicularis, n. sp. (PI. II., Fig. 14). 



Zoarium encrusting. Zooecia quincuncial, elongated, quadrate, 

 but broader distally. Thyrostome inversely subtriangular, curved 

 distally, with a small mucro in the proximal angle ; sides with a 

 mucro on the distal ends, forming a small circular channel or 

 opening on each side. Surface with vermiform markings, at the 

 end of some of which are pores. 



Locality. — Cape Otway (J. Dennant). 



I at first assigned this species to Mucronella on account of the 

 mucro in the proximal part of the thyrostome, but the character 

 of the whole thyrostome is so peculiar that I have formed a new 

 genus for its reception, as it cannot be included in any existing 

 genus ; the distal part is a simple curve in the median portion, 

 but at each end the margin goes round in a small circular, 

 almost closed, curve, and then turns sharply proximally forming 

 a mucro on each side in so doing, and in the rounded proximal 

 angle there is a small mucro. 



Porina tuberculosa, n. sp. (PI. II., Fig. 15). 



Zoaria cylindrical. Zooecia in longitudinal series, large, 

 elongated, quadrate, separated laterally by distinct, raised 

 margins. Surface covered with scattered tubercles. Thyrostome 

 transversely elliptical ; peristome elevated, thin, witli a very 

 large elliptical opening below it, the upper margin of which is 

 curved and overlaps the opening. A sessile avicularium on each 

 side of the thyrostome, and equally elevated with it. 



Locality. — Gellibrand River (A. E. Kitson). 



This is somewhat similar to Porina cribraria, McG. It differs, 



