Canterbury and Westland. 261 



situated entirely along the western watershed of the Southern Alps. 

 Gradually it becomes broader, and, near Browning's Pass, crosses to 

 the eastern side of the central chain, whence it continues to be largely 

 developed as far as "Whitcombe's Pass, the rocks on the western side of 

 the Pass included. The summits of the Southern Alps continue to be 

 generally formed of rocks belonging to this zone, till we reach Mount 

 Cook, which consists of beds pertaining to the next, or Mount Torlesse 

 formation. South of Mount Cook, in the Sealy range, the "Waihao 

 formation again becomes greatly developed, now increasing much in 

 breadth, and being divided into two portions by beds of great thickness 

 overlying them, which appear principally in the River Hunter, the 

 eastern belt of the "Waihao formation being the narrowest one. 

 Another zone of the same formation enters the Province of Canterbury 

 from the south, between the junction of the Hakataramea with the 

 "Waitaki and the mouth of that river, consisting of a series of ranges 

 from 2,000 to 3,500 feet high, which are the apex of an anticlinal or 

 saddle-back arrangement. They sometimes appear as high table-land, 

 into which the rivers have cut deep gorges, and are bounded and over- 

 laid on both sides by younger rocks. These younger rocks rise to higher 

 mountain chains, on the eastern side as the Hunter, on the weatern as 

 the Hakataramea ranges, situated on the right or western bank of the 

 Hakataramea river. They continue as far as Fox Peak on the western 

 side of the Opuha plains, getting gradually narrower where they 

 disappear below beds belonging to the Mount Torlesse formation. 

 Small outliers occur on both banks of the Pareora, Opihi, and 

 Kakahu rivers, about their middle course. Judging from the litho- 

 logical character of the altered beds occurring there, another outlier 

 exists in Banks' Peninsula. 



Position op Strata and Testtie or Eocks. 

 Near the banks of the Taramakau, the rocks consist of fine light 

 coloured silky clay-slates, nodular schists (Pruchtschiefer), and many 

 other varieties belong to this group, alternating with quartzose schists, 

 which dip to the south-east at an angle of 50 to 55 degrees. ]S"ear 

 the sources of the river Styx, a tributary of the Hokitika, the same 

 slate formation occurs in great abundance, but is sometimes more 

 micaceous. There it also dips to the south-east, but at an angle of 

 70 degrees. Crossing into the head-waters of the Arahura, by the 

 "Wooded saddle, where the "Waihao formation becomes more developed, 

 the strata in Mount Sale are largely interlaminated with quartz, and 



