456 Transactions. — Geology. 



examination of the district in 1885. He collected a great 

 deal of new evidence as to the stratigraphical position of the 

 Parnell grit, which he was inclined to think inferior to the 

 Orakei greensand ; identified the Parnell grit with the Chelten- 

 ham breccia on palasontological grounds ; traced the whole 

 series eastward to the Papakura limestone ; and concluded 

 that the Waitemata series was unconformable to the Cretaceo- 

 tertiary beds. His final classification was as follows : — 



Upper Miocene. 



1. " Fort Britomart " shales. 



2. Parnell grit and Waitakerei breccias. 



Lower Miocene. 



3. Turanga greensands. 

 Orakei Bay greensand. 



4. Papakura limestone. 

 Cape Rodney grits. * 



Sir James Hector still thought the series should be 

 divided at the Parnell grit. He dissented from Mr. Park's 

 view that the Cheltenham breccia was the northerly exten- 

 sion of the Parnell grit, considering the Cheltenham breccia 

 and the other volcanic beds to the north of the harbour of 

 Pliocene age, and quite unconformable to the Waitemata 

 series.! 



Mr. Park, in 1889, upheld his views as given above.]: 

 Since 1889 nothing of importance has been published on 

 the volcanic beds of the Waitemata series. The view adopted 

 in the present paper has been already indicated in the intro- 

 duction. 



3. The Volcanic Beds of the Series. 



As the volcanic beds at Cheltenham and Parnell are the 

 thickest, most fossiliferous, characteristic, and widely spread 

 beds of the series, and their stratigraphical position and age 

 have been a subject of much dispute, most of the paper will 

 be devoted to a consideration of them. The evidence tends to 

 show that they are distinct beds, though Mr. McKay and Mr. 

 Park consider them identical, and Mr. Park writes that he 

 has " conclusively proved " their identity. Sir James Hector 

 considers the Cheltenham breccia to be Pliocene, so that it 

 will be necessary to give in some detail reasons for suppos- 

 ing it to be Lower Miocene, or even Oligocene. With regard 

 to its source, I will give evidence tending to show that it 

 probably came from the Waitakerei vents. The chief point 



* Geological Reports, 1885. 

 -( Geological Reports, 18S5-S6. 

 I Trans. N.Z. Inst., 1889. 



