Fox. — The Waitemata Series. 493 



to scatter their debris over the floor of the Auckland sea ; and 

 it is to these we owe the Parnell grit. At a later period the 

 volcanic forces became quiescent, the Miocene strata were 

 raised and extensively denuded, and between the two former 

 lines of volcanic activity arose scores of puys, which covered 

 the older strata with tuffs and basic lavas, and distorted the 

 beds, raising them sometimes, perhaps, from the sea ; though 

 I believe the majority of these puy cones arose on the land. 

 One conclusion of interest is that these areas of volcanic 

 disturbance were areas of subsidence, not elevation.* 



It is possible that the Waitakerei outbursts were at first 

 submarine, and the opening phase may have been one of 

 elevation. But while the vents discharged their contents 

 the sea-floor gradually sank. It was only when volcanic 

 energy had completely died away that the consolidated sand- 

 stones, shales, and tuffs were thrown into long gentle anti- 

 clines and synclines, to be denuded by the atmospheric forces, 

 until, after another phase of volcanic history of quite a 

 different type, they again began to sink beneath the waves. 



* See Sir A. Geikie : " Ancient Volcanoes of Great Bricain," vol. ii., 

 p. 470. 



