Palaeontology of the Older Tertiary. 325 



clays and clays of Orphanajre Hill, near Geelong, and along 

 the Lower Mnoral^ool Valley ; Curlewis clays, and Belmont, near 

 Geelonp: ; Newport shaft ; Murgheboluc, Barwon River ; Inver- 

 leigh ; Shelford ; Lower Beds of Muddy Creek, near Hamilton, 

 AVestern Victoria; clays of the coastal sections Gellibrand 

 River. — Balcombian (except Curlewis and Belmont. — Bar- 

 wonian).^ — Eocene. 



Clays of the middle zone of the Sprinoj Creek series, Bird 

 Rock Bluff, near Geelong-. — Jan Jukian. — Eocene. 



Observations. — This is a well marked and characteristic little 

 species entirely different from any other of our described 

 species, and has been frequently quoted as C. clathrata, Tate, 

 but as that name was never more than a manuscript one 

 and as it ha® already been several times preoccupied for both 

 recent and fossil species of this genus, the necessity for a new 

 name is obvious. 



Columbella apppoximans, sp. nov. (PL XVIIL, 

 Figs. 12, 13). 



Description. — Of similar habit to the foregoing species, C. 

 balcombensis, with ;i slightly exsert tip to the three smooth 

 embryonic whorls succeeded by four other whorls, it differs 

 strongly in its sculptm-e, bearing fewer bowed or backwardly 

 curved costulae with very faint spiral lineations except towards 

 the extreme anterior of the body-whorl. There are about thir- 

 teen costulae on the first whorl increasing to about twenty-two 

 on the penultimate whorl. Outer lip strongly evaricose, and 

 externally much more finely lirate than C. balcombensis, canal 

 and columella also shorter. The contrast between the stronger 

 development of the costulae and the weaker development of the 

 spiral sculpture loses entirely for this species the clathrate ap- 

 pearance so characteristic of the foregoing. 



Dimensions. — Length, 7 mm. ; breadth, 3 mm. ; length of 

 aperture and canal, 3 mm. 



Locality. — Clays of the Old Cement Works, Balcombe's Bay, 

 Mornington.- — ^Balconibian — Eocene. Also Curlewis, near Gee- 

 long. — Barwonian. — Eocene. 



