428 Transactions. 



" clay-schists " of Lower Silurian age. In his " Geoiogy of 

 Otago " (1875) Hutton agrees with Hector, and calls the 

 schists (Wanaka series) " Lower Silurian," but in his " Sketch 

 of the Geology of New Zealand "* he gives their age as Or- 

 dovician. In a paper published in the ' ' Transactions of the 

 New Zealand Institute," 1899, he classes the schists as Ar- 

 chaean. 



The Tertiary sandstones overlying these schists form the 

 surface of a large block of country to the south and west of 

 the Peninsula. On the Peninsula itself it is almost every- 

 where covered by tremendous outflows of lava. However, 

 along the shore of the Pacific Ocean on the south side of the 

 Peninsula it outcrops, forming cliffs on the top of which are 

 the lava-flows. It is for the most part composed of rounded 

 grains of quartz and finer detritus, and is in many places stained 

 with oxide of iron, doubtless in part derived from the decom- 

 position of the lavas above. It outcrops underneath the basalt 

 at Sandy Mount (see map) at about 100 ft. above sea-level. 

 In the " Geology of Otago " Hutton says that above the coal- 

 deposits which occur in the lower portions of the series are a 

 series of conglomerates (p. 48). These occur as outcrops at 

 Kaitangata, but do not outcrop at Dunedin. In the early part 

 of the winter of 1904 the writer was present at boring opera- 

 tions conducted on the flat comprising the lower part of 

 Dunedin. A steam percussive borer was used, which in most 

 cases reduced the rock pierced to fine powder. After passing 

 through about 50 ft. of harbour-silt and volcanic rock in a 

 decomposed state, and 100 ft. of sandstone, a very hard ma- 

 terial was encountered which the borer would scarcely touch. 

 Rounded and broken fragments of quartz were brought up by 

 the pump, which evidently came from a quartzose conglo- 

 merate exactly similar to that found above the Kaitangata 

 coal. Thus it seems that this coal exists not far below 150 ft. 

 from the surface. 



The sandstone is undoubtedly derived from the denuda- 

 tion of the schistose country at the back. The quartz pebbles 

 forming the conglomerate above referred to are undoubtedly 

 schistose in their origin, showing in places foliation-planes in 

 the separate pebbles. The age of these sandstones is given by 

 Hector as Cretaceo-tertiary in his work above referred to. 

 Hutton (" Geology of Otago ") classes them with the Oamaru 

 series of Oligocene age. In the outcrop along the cliffs to the 

 west of Dunedin fragmentary remains of fossil shells are to be 

 obtained lrom the cliffs, notably Pecten hochstetteri, which 



* Quart. Journ. Geol. Soc, May, 1885. 



