1873.] HETT0N — YOUNGER FORMATIONS OF NEW ZEALAND. 373 



References. — Buchanan, Trans. N. Z. Institute, ii. p. 154 (Sandy 

 Bods). 



Remarks. — The pumice plains of the North Island and the shingle 

 deposits of the Canterbury and Southland plains must probably be 

 referred in part to this period and in part to the next. 



Pliocene Period. 

 Newer Pliocene or Whanganui Group. 



Number of species determined 89 



„ of recent species 68 



,, passing up into the Pleistocene formation 48 



., passing down into the Awatere group 29 



„ confined to the group 8 



Percentage of recent species , 76 



Localities. — Worth Island: Shakespeare's Cliff, "VVhanganui; Patea. 

 South Island : None known. 



References. — Buchanan, Trans. N. Z. Inst. ii. 164 (Blue Clay). 

 Crawford, Trans. N. Z. Inst. ii. 343 (6 in part). Hochstetter, New 

 Zealand, 1867, p. 61 (c). Mantell, Quart. Journ. Geol. Soc. iv. 1848, 

 p. 239 (Blue Clay). 



Remarks. — This group, which is only found in the north-western 

 part of the Province of Wellington, but extends, perhaps, into 

 Taranaki, consists principally of blue clay. A species of Natica is 

 found in it which ranges down to the Ototara group, and which is very 

 like Mamilla carnatica of the Cretaceous rocks of India, but inter- 

 mediate between that shell and N. mamilla of Polynesia. 



Older Pliocene or Lignite Group. 



No marine beds of this age are known in New Zealand. 



Localities of Freslnvater Beds. — North Island: Plastic clays, with 

 lignite of the Lower Waikato and Drury. South Island : Lacustrine 

 deposits of the Province of Otago, with lignite. 



References. — Hector, Quart. Journ. Geol. Soc. 1865, p. 125 (d), 

 p. 128 (ii. 1). Hochstetter, New Zealand, 1867, p. 62 (a and b). 

 Hutton, Geol. Reports, 1871-72, Southland District, p. 112 (Qua- 

 ternary lignites). 



Remarks.— The last great extension of the New-Zealand glaciers 

 must, I think, be referred to this period, as there is no evidence of 

 a colder climate having existed during either the newer Pliocene or 

 the Pleistocene periods ; consequently the old moraines, with Moa- 

 boncs, of the Canterbury province are probably of this age. 



Miocene Period. 



Number of species determined 135 



„ of recent species 40 



„ passing up into the Pliocene formation 31 



,, passing down into the Oligocene formation .... 24 



,, confined to the formation 50 



Percentage of recent species 29 



