Mulgan.- —The. Waitemata Series. 



419 



It muse be uoted that both these and the Parnell ash-beds 

 are of a fairly constant texture, and contain no large included 

 fragments. As previously stated, the Point Acheron outcrop 

 can only be seen as a short platform on the beach. It cannot 

 be connected stratigraphically with the exposures at Point 

 Erin ; but the distance separating the two places is not great, 

 and in composition the bands are identical. It seems an 

 obvious conclusion, therefore, that the Ponsonby outcrops are 

 connected. 



Fig. 2. 



Ft. Erin 



E <- 



■w Shelly Beach Pt 



Section from Point Erin to Shelly Beach Point, showing connection 

 between the two outcrops of grit : 1. Volcanic grit. 2. Sandstones 

 and shales. 



It is impossible to correlate with certainty the Parnell 

 ash-beds and those occurring at Point Erin, because — (a) A 

 great portion of the City of Auckland is built on the land 

 lying between them ; (b) the intervening strata are much 

 disturbed ; (c) most of the intervening country is covered 

 with tuff from some of the Pleistocene volcanic vents. But 

 the great similarity in the material composing all these beds ; 

 the fact of there being an undoubted connection between the 

 Parnell and St. Helier's Point outcrops on the one hand, and 

 on the other between the various exposures at Ponsonby ; and 

 the further fact that, whereas the distance from Judge's Bay 

 to Tamaki Point is upwards of three miles, that from St. 

 George's Bay to Point Acheron is considerably less — would 

 at least point towards the very great probability of the 

 Ponsonby outcrops being extensions of those found at Parnell : 

 — that is, the outcrops of grit occurring along the southern 

 shores of the Auckland Harbour are merely different exposures 

 of the same band. 



Section V. — Grit -beds on the North Side of the 



Auckland Harbour. 



Across the harbour, just below Takapuna Point, at a dis- 

 tance of some two miles and a half from Judge's Bay, there 

 occurs another exposure of volcanic grit. This formation, 

 known as the " Cheltenham Beach beds," consists of a band 

 of about 12 ft. in thickness containing both coarse and fine 

 material. At the bottom is a layer a few inches in thickness 

 of coarse grit or fine conglomerate, the particles being from 



