452 Transactions. — Geology. 



Permo-carboniferous — 

 Mount Mary series. 



(Syn. : Te Anau series, Hector ; Kaikoura formation 

 Hutton ; Lower part Mount Torlesse formation, Haast.) 



Carboniferous — 



Kakanui series. 



(Syn. : Kakanui series, Hector and Hutton ; Tuamarina 

 formation, Hutton; and Waihao formation, Haast.) 



Eelations to Adjoining Rock-formations. 



The Waitaki River, between the Kui-ow and Awahokorao, 

 runs along the axis of an anticUne of ciaystones and sand- 

 stones, in which Mr. McKay discovered numerous remains 

 of Inoceramus , inckiding an almost perfect example found 

 near the mouth of the Hakataramea.* 



Mr. McKay shows these rocks to be unconformable to the 

 altered Kurow rocks, and refers them to the Maitai series of 

 the Geological Survey, of supposed Carboniferous age. 



As the "Kurow schists" have been shown to be asso- 

 ciated with rocks of Permo-carboniferous age, it necessarily 

 follows that the Waitaki Valley rocks, which overlie these 

 unconformably, must be of subsequent date ; and the pre- 

 sence of the Secondary genus Inoceramus clearly indicates 

 that they must be referred to the Jurassic system, a position 

 quite in harmony with my conclusion respecting the Jurassic 

 age of the Maitai series in Nelson. 



The Mount Mary series fills a gap in the New Zealand 

 geological record, and, furthermore, furnishes for the first time 

 reliable data by means of which the age of the Kurow 

 phyllites can be ascertained. 



The classification which my investigation of the Lower 

 Mesozoic and Upper PaltEozoic rocks in the past three years 

 has led me to adopt is as follows : — 



Jurassic — Mataura series. 



Triassic — Shaw Bay series — 



{a.) Athyris (or Clavigcra) beds. 



(b.) Mytilus and Monotis beds. 



(c.) Trigonia beds. 



(d.) Halobia iovimeli beds. 



(e.) Spiriferina beds. 



(/.) Nugget Point plant beds. 



Permo-carboniferous — Mount Mary series. 

 Carboniferous — Kakanui series. 



• Reps. Geol. Expl., 1881, p. 78. 



