Park. — Age and Belations of Neiv Zealand Coalfields. 415 



In the line of section from Shag Point Coal-mine across 

 Puke-iwi-tahi the thickness of the series is about 2,200 ft., of 

 which the Horse Eange conglomerates comprise probably 

 about 1,500 ft. 



In his paper " On the Relative Ages of New Zealand Coal- 

 fields " Captain Hutton states that in his opinion the coalfields 

 ■of the colony may be grouped according to their age into four 

 series, as follows :— * 



4. Pareora series, including coalfields of (a) Mokau, {b) 

 Waihao, (c) Waitaki, ((/) Pomahaka, {e) Dunstan(?). 



3. Oamaru series, including coalfields of (a) Bay of Islands, 

 {b) Whaugarei, (c) Drury and Lower Waikato, {d) 

 Nelson and Motupipi, (e) Kakahu, (/) Green Island 

 and Saddle Hill, {g) Tokomairiro and Kaitangata, 

 (//) Nightcaps, (i) Orepuki. 



2. Waipara series, including coalfields of (a) Malvern Hills, 

 (b) Mount Somers, (c) Shag Point, (d) Mount Hamil- 

 ton. 



]. Amuri series, including coalfields of (a) Pakawau, [b) 

 Wangapeka, (c) Westport, {d) Greymouth, (e) Reef- 

 ton. 



Captain Hutton considers that the Mokau coalfield belongs 

 to the Pareora series. But is it so? On the other hand, he 

 places the Lower Waikato coals in the Oamaru series. I 

 am satisfied that whatever is the age of the Waikato coals is 

 also the age of the Mokau coal. 



Near Huntly and Taupiri the coal passes below marly 

 greensands containing a marine fauna that seems the same as 

 that overlying the coal at the Bay of Islands and Hikurangi. 

 The greensands are followed by sandy clays, generally fora- 

 miniferous, and these are in turn overlain by calcareous sand- 

 stones, which pass insensibly into a hard limestone towards 

 the south and west. The limestone contains Scalaria lyratx, 

 a Lima, Pecten hochstetteri, and Meoma craufiordi, which 

 are characteristic of the Oamaru stone elsewhere. In 1885 I 

 traced it from the Waikato River at Taupiri westward to 

 Raglan and southward to Waipa, Kawhia, Te Kuiti, Upper 

 and Lower Mokau. In the Raglan district it is a yellowish- 

 brown sandy limestone resembling the Weka Pass and Ocotara 

 stone, but proceeding south it passes into a hard shelly lime- 

 stone. It should be noted, however, that the stratigraphical 

 succession of the underlying beds down to the coal at the 

 base of the series is everywhere remarkably uniform. 



This series, which I now refer to the Oamaru series, is 

 everywhere in this region, as follows : — 



* Trans. N.Z. Inst., vol. xxii., 1889, p. 387. 



