280 



Tlialotia exigua, Tenlson-Woods. 



1879. Tlialotia exigua, Tenison- Woods, Proc. Linn. Soe. N.S.W. vol. iii. 



p. 235, pi. XX. fig. 11. 

 1889. Tlialotia exigua, Dennant, Trans. Roy. Soc. South Aust. vol. xi. p. 48. 



Shell small, spire much elevated ; whorls nearly flat, furnished 

 •with four or five rows of closely-set spiral granulations ; suture 

 not well marked ; last whorl subangulate at the periphery ; base 

 having numerous, small spiral threads ; aperture nacreous, 

 quadrate, flat in front ; outer margin obliiiue ; columella with 

 a single dentiform fold. 



It is closely allied to the living T. conica, Gray. 



Dimensions. — Length 8 mm. ; breadth 5 -5 mm. 



Form, and Loc. — Eocene : Muddy Creek, Victoria. 



G. 9485. Three examples of the adult. Purchased 



Genus BANKIVIA (Beck), Krauss. 



[Die Siidafrikanisclien Moll. 1848, p. 105.] 



Shell imperforate, elongate, multiwhorled, conical, slightly 

 nacreous ; aperture small ; columella twisted, truncate anteriorly. 

 Type. — Bankivia varians, Beck. 



Bankivia fasciata, Menke. 



1830. Phasianella fasciata, Menke, Synops. Math. Moll. p. 141. 



1830. Phasianella fubninata, Menke, id. p. 141. 



1830. Phasianella nndatella, Menke, id. p. 141. 



1848. Bankivia varians (Beck), Krauss, Die Siidafrikanischen Moll. p. 105, 



pi. vi. fig. 1. 

 1851. Bankivia piirpurascens, A. Adams, Proc. Zool. Soc. p. 171. 

 1851. Bankivia major, A. Adams, id. p. 171. 

 1861. Bankivia nitida, A. Adams, id. p. 172. 

 1886. Trochus (Bankivia) fasciatus, Watson, Voy. "Challenger," Zool. 



Gasteropoda, vol. xv. p. 64. 

 1889. Cantharidiis [Bankivia) fasciatus, Pilsbry, Tryon's Manual of 



Conchology, vol. xi. p. 139, pi. xl. fig.s. 28-33. 



A very variable species, as the synonymy above quoted 

 indicates. The columella of the specimens in the Museum 

 collection is more excavated and much more strongly twisted 



