Hutton. — On new Tertiary Shells. 313 



the Waipara System, what is the age of the " chalk-marls and hydraulic 

 limestone " which underlie them unconformably ? These are also considered 

 by Dr. Hector and Mr. McKay to be cretaceo-tertiary, and certainly they 

 are not like any rocks in New Zealand that are older than the Waipara 

 System. Again, if the Orakei beds belong to the Waipara System, what is 

 the age of the green sandstones of Turanga and Papakura, which both Mr. 

 Cox and myself have shown to underlie the Orakei Bay beds unconformably ? 

 Dr. Zittel considered the Papakura series to be of eocene age, that is, to 

 belong to the Oamaru System, and if this be correct the Waitemata series 

 must belong to the Pareora System. This conclusion is quite in accordance 

 with the evidence, both stratigraphical and palaBontological, at Komiti Point, 

 and at Mahurangi, and is not contradicted by the fact that the Mercer beds 

 are apparently conformable to the underlying marls, for it is quite possible 

 that two systems may be conformable at one place although unconformable 

 at other places. 



It appears then (1.) That there is no evidence that the Orakei Bay beds 

 are older than the Parnell grit ; they may or may not be so ; (2.) That 

 there is no evidence of any unconformity in the Waitemata series between 

 Auckland and the Tamaki ; and (3.) That the evidence, both stratigraphical 

 and palseontological, is altogether in favour of the Orakei Bay beds belonging 

 to the Pareora System. 



Art. XL. — Descriptions of new Tertiary Shells. Part I. 



By Captain F. W. Hutton, F.Gr.S. 



[Read before the Philosophical Institute of Canterbury, 27th November, 1884.] 



Plate XVIII. 



During the past year I have received several collections of fossils from Mr. 



S. H. Drew, of Wanganui, and from Mr. A. Hamilton, of Petane, near 



Napier, and I now offer descriptions of the new species so far as I have 



made them out. There are, in addition, a few species which, although not 



known in New Zealand, are living in Australia or Polynesia, e.g. Drillia 



alabaster, Reeve. 



Ringicula uniplicata. 

 Shell minute, ovate, transversely finely striated. Whorls 4, those of 

 the spire small and smooth. Aperture narrow, obliquely notched in front ; 

 the outer lip thickened, varicose ; columella with a strong anterior plication. 

 Length, '08 inch. 

 Locality. Petane. 



