Tertiary Polyzoa of Victoria. 73 



P Leppalia bisinuata, n. sp. (PI. IX., Fig. 20). 



Zooecia quadrate, flat, with a row of large pores round the 

 margin which is narrow and slightly raised. Thyrostome horse- 

 shoe-shaped with a projection on each side near the lower margin, 

 the centre of which is incurved, forming a sinus in each lower 

 angle. A small oval avicularium, with a bar, below the thyros- 

 tome. 



Locality. — Mitchell River (J. Dennant). 



A single specimen. In two of the zooecia figured the avicu- 

 larium is perfect, in one it is only partly developed, and in the 

 fourth it is absent. This I at first supposed to be a Smittia 

 near S. reticulata ; on further examination the form of the thy- 

 rostome, as shown on a larger scale in Fig. 20a, was found to be 

 Lepralian of a type similar to L. cleidostoma, Smitt., but the 

 inward curvature of the lower or proximal margin forming a 

 sinus in each corner is peculiar, it simulates the "lyrula" found 

 in most of the Smittiae, but that is always internal or below the 

 level of the thyrostome, this is part of the margin itself, it may 

 require a new genus for its reception near Smittia, distinguished 

 therefrom by the double sinus. 



Tpypocella, nov. gen. 



Zooecia elongate, flat. Thyrostome orbicular, with an acute 

 sinus in the proximal margin formed by the incomplete junction 

 of the cell wall. No peristome. 



Tpypocella excavata, n. sp. (PI. IX., Fig. 21). 



Zooecia elongate, irregularly hexagonal, with a row of large 

 pores round the margin. Central portion concave. Thyrostome 

 orbicular with a very acute sinus. A large circular pore on each 

 side a little below the thyrostome. 



Dorsal sui*face with large pores. 



Locality. — Spring Creek (T. S. Hall). 



A single sjoecimen in good preservation. I cannot assign this 

 species to any of the existing genera of the Escharine group on 

 account of the very peculiar structure of the thyrostome, which is 

 without any raised mai'gin or peristome ; it appears as though 



2a 



