Fox.- — The Waitemata iSeries. 457 



of interest with regard to the Parnell grit is whether it is 

 above or below the Orakei Bay greensand, because the latter 

 is a fossihferous bed which is allowed to be Miocene. Mr. 

 Park felt inclined to place it below, although admitting the 

 evidence inconclusive, and he has since classed it as Eocene. :;: 

 But a large amount of new stratigraphical evidence will be 

 given which leads me to think that it is really above the 

 Orakei greensand, and therefore Miocene. Its source is an 

 open question ; it may have come from the Waitakerei, but 

 there is evidence in favour of its having come from the Coro- 

 mandel vents. There are at least two other volcanic beds. 

 One of these really consists of a group of tufls separated by 

 thin layers of shale. They are well developed at Wairau 

 Creek, and so I have called them the " Wairau tuffs." The 

 other bed is a feldspathic tuff, developed best at Ponsonby, 

 and called throughout the " Ponsonby tuff." These can be 

 dealt with more shortly. 



I consider that the thick volcanic breccias on the west 

 of the Waitakerei Eange should really be included in the 

 Waitemata series, but I have not been able to examine 

 them sufficiently to include a discussion of them in this 

 paper. 



4. Are the Cheltenham Breccia and the Parnell Grit 



distinct Beds ? 



The study of the volcanic outcrops at these places has led 

 me to the conclusion that these beds are distinct. The evi- 

 dence is considerable, consisting of a number of facts which 

 are cumulative. Before giving them it will be advisable to 

 give the evidence in favour of the identity of the beds. 



Mr. Park, in 1885, came to the conclusion that the outcrop 

 at Cheltenham, on the north side of the harbour, was simply 

 a northerly extension of the outcrop at Parnell, on the south 

 side. Sir James Hector dissented from this, and wrote : 

 " The Parnell grit, which has been much relied on in dis- 

 cussions concerning the Waitemata formation, has in many 

 cases been confounded with the volcanic grits and con- 

 glomerates in other parts of the district "t — i.e., with the 

 Cheltenham breccia. Mr. McKay, too, who had been the 

 first to suppose the beds identical, wrote : " As a consequence 

 of my admission that the Parnell grit does or should pass 

 under the Fort Britomart and Calliope Dock beds, and of 

 the observed fact that the breccias north of Cheltenham 

 Beach overlie them, I am forced to agree with Sir James 

 Hector that the Parnell grit and Cheltenham breccia do not 



* u i 



Thames Goldfields " : Park and Kutley, 1897. 

 f Geological Reports, 1885-86. 



