49
towards the Rangitikei and Pohangina Rivers. As pumice-sandsthey cover the elevated country round the base of Tongariro andRuapehu , and thence form the sloping plain that stretches to the Bay of Plenty , Lake Taupo , and the valley of the Waikato River . Theyfurther flank the Ruahine Range on the east side, and extend north asfar as Moeangiangi, and, besides appearing as isolated patches between,form the low hills surrounding Poverty Bay. Where they flank theRuahine Ranges they have a great thickness, and, being there ofmarine origin, are highly fossiliferous. In that district they have alsobeen involved in extensive structural movements, so that in manyplaces they have been completely overturned. Elsewhere they •arenearly horizontal, although the marine beds have been locally raisedto an altitude of 300 feet above sea-level.
In the South Island their principal development is on the WestCoast, between Lake Brunner and Bruce Bay, and in the CanterburyPlains, where they fringe the range between Timaru and the WaiparaRiver. They also occur in the Hurunui Plains; around Lake Tripp;at the outlets of Lakes Ohau, Pukaki, and Tekapo; fringing the olderCarboniferous rocks in the Mackenzie country; from the Wanakaand Hawea Lakes as far south as Wakefield ; the upper lacustrinegravels of the Manuherikia and Maniototo Plains ; also between LakeTe Anau and the Mararoa River; and in the Southland Plains, a partof which is composed of these beds.
Fig. 6.
a. Te Aute series, b. Taueru series.
The marine beds of this age are limited in their extent to thesouthern and eastern districts of the North Island , where, on the•south slope of the Kaimanawa Range, they have a full development upto 3,700 feet above the sea-level from the coast-line at Wanganui.
In the South Island they occur as patches, inland from Timaru ,between Peel Forest and the Waitaki River; at the mouth of theWaipara; at Ross; to the south of Greymouth ; and in Nelson,from Lake Rotoiti to the sea; but here, as at many other places,these beds are often represented by gravel conglomerates that, frqmthe absence of fossils, have not been distinguished from the preceding-formation.
Their mineral character is a series of sandy, calcareous, andD