196 



Spiralis tertiaria, spec. nov. Plate xx., figs. 12a — 12c. 



Shell sinistral, thin, shining, transparent ; subglobosely 

 depressed, nmbilicated. The last whorl is convex, rapidly 

 enlarging, regularly curved, except near the suture, where it is- 

 rapidly descending ; spire sunken, with the apical whorls rising 

 to the level of the last whorl. Umbilicus small. Peristome 

 thin, simple, a little reflexed at the umbilicus. Surface sculp- 

 tured with fine sigmoid lines. 



Diameter, one millimetre. 



Localities. — Lower beds at Muddy Creek and blue clays at 

 Schnapper Point. 



Explanation of Plates. 



]S\B. — The figures are of the natural sizes except when other- 

 wise stated. 



Plate XIV. 



1. Cardium Victoria?, Tate. Muddy Creek, a, Left valve ; 



b, enlargement of surface near the ventral margin. 



2. Cardium hemimeris, Tate. Adelaide, a, Right valve ; b, 



enlargement of portion of anterior half (not correct) > 

 and c, of posterior half. 



3. Cardium moniletectum, Tate. Adelaide, a, Left valve ; b, 



enlargement of surface. 



4. Yerticordia rhomboidea, Tate. River Murray Cliffs. En- 



larged. 



5. Chama lamellifera, Tenison- Woods. Schnapper Point. a T 



Attached valve ; b, free valve. 



6. Montacuta sericea, Tate. Muddy Creek. Enlarged. 



7. Chione propinqua, T. Woods. Muddy Creek. 



8. Chione propinqua, T. Woods. Table Cape. 



9. Dosinia Johnstoni, Tate. Muddy Creek. 



10. Diplodonta subquadrata, Tate. Muddy Creek, a, Left 



valve, and b, dorsal aspect of the same. 



11. Dosinia imparistriata, Tate. Adelaide. 



12. Dosinia Johnstoni, Tate. Muddy Creek, a, Left valve of 



an adult shell, and b, dorsal aspect of the same. 



13. Yerticordia pectinata, Tate. Muddy Creek. Enlarged. 



14. Cytherea paucirugata, Tate. Muddy Creek. 



15. Yenerupis paupertina, Tate. Muddy Creek. Slightly en- 



larged. 

 10. Cytherea tenuis, Tate. Adelaide. 

 17. Chione subroborata, Tate. Muddy Creek, a, Left valve - r 



b, dorsal aspect of right valve. 



