90 MAEGINELLA. 



by Professor Tate; but it lias a smaller and shorter spire, and 

 is more gibbose. 



Dimensions. — Length 3"5ijim.; breadth 2-75 mm.; length of 

 aperture 3 mm. 



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



G. 4209. A series exhibiting stages of growth. 



Presented by John Bennant, Esq. 



Marginella (Glabella) cassidiformis, Tate. 



1878. ilarginella cassidiformis, Tate, Trans. Phil. Soc. Adelaide, 1877-8, 



p. 91. 

 1889. Marginella cassidiformis, Dennant, Trans. Eoy. Soc. South Aust. 



vol. xi. p. 43. 



Shell small, tumid, conical, solid; spire of medium height, two 

 to three whorls, ornamented by bold, obtuse, distant, longitudinal 

 plications, nodose at the subangular periphery ; suture distinct ; 

 aperture narrow, attenuated posteriorly, truncated anteriorly; outer 

 margin abnormally thickened and slightly reflected, not crenu- 

 lated ; columella quadriplicate. 



The bold longitudinal plications on the whorls, and stunted, 

 solid form, serve to distinguish this from any other Australasian 

 Marginella. It differs from M. aldinga, Tate, in its general shape 

 and form of aperture ; the species resemble each other, however, 

 in being nodosely plicated on the periphery of the whorls. 



Dimensions. — Length 4 mm. ; breadth 3 mm. ; length of aper- 

 ture 2-75 mm. 



Form, and Loc. — Eocene : Aldinga, South Australia. 



G. 9342. Several examples of the adult. Purchased. 



Subgenus CRYPTOSPIRA, Hinds. 



[Proc. Zool. Soc. 1844, p. 76; Belcher, Voy. " Sulijhur," Mollusca, vol. ii. 

 1844, p. 46.] 



Shell ovate or globose ; spire very short or completely hidden ; 

 columella with several plications ; anterior extremity covered by 

 a callosity passing from the outer margin round the canal, and 

 extending over the front of the columellar border; outer margin 

 thick, and often crenulated. 



Type. — Marginella tricincta, Hinds. 



