164 Transactions. 



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Duntroon or Kurow districts, except at Wharekuri, where the fossils are 

 abundant. No junction has been observed between the greensands and 

 the underlying Ngaparan coal-rocks except at Black Point. There appears 

 to be a very gradual transition from the quartz conglomerates and fine 

 micaceous quartz sands into the overlying greensands, the glauconite of 

 the latter becoming very abundant, and the quartz and mica gradually 

 diminishing. In the Maruwenua cliffs near Duntroon the limestone over- 

 lying the greensands is very glauconitic, and at White Rocks and the 

 " Earthquake " this glauconitic lower portion of the limestone increases 

 greatly in thickness. In the Landon Creek area also this glauconitic 

 portion of the limestone shows a thickness of 50 ft. below the Hutchinsonian 

 horizon (refer to Park, 1918, p. 46). It is noticeable that where the lime- 

 stone is very glauconitic the brachiopods are abundant. From the glauconitic 

 portion of the limestone near Duntroon, as well as from a higher horizon 

 in the limestone at White Rocks and the " Earthquake " in the Waitaki 

 Valley, a brachiopod fauna ' similar to that occurring in the glauconitic 

 portions of the limestone at Landon Creek, in the Oamaru district, has 

 been found ; and the evidence available strongly favours the view that 

 both rocks are Ototaran. There is no evidence to show that the lime- 

 stone of the Waitaki Valley is Hutchinsonian. The .base of the Otekaike 

 limestone at Wharekuri, Otiake, and Otekaike is not seen in any of the 

 sections exposed. It is probable that if the base of the limestone were not 

 hidden by the gravel deposits we should find the same brachiopod fauna 

 that characterizes the base of the limestone at Maruwenua. The fossil- 

 iferous beds overlying the limestone at Wharekuri, at Otiake, at Otekaike, 

 at Duntroon, and at Station Peak are at the same horizon, and represent 

 the Hutchinsonian-Awamoan horizon of the Oamaru district. These rocks 

 pass up into poorly fossiliferous calcareous mudstones. 



In the Oamaru district the Ngaparan rocks are overlain by fossiliferous 

 glauconitic calcareous greensands, which in turn are overlain by the 

 Waiarekan tuffs, followed by interbedded tachylite tuffs and diatomaceous 

 deposits, which are overlain by the Ototaran limestone, followed .by the 

 Hutchinsonian and Awamoan beds. In the Papakaio district the succession 

 is similar, although the Awamoan beds have been denuded, except at 

 Pukeuri, where all observers agree that they follow the Hutchinsonian. 

 In the Waitaki Valley the succession is not complicated by the presence 

 of volcanic rocks, nor are there diatomaceous beds ; but all the evidence 

 available goes to prove that the greensands below the limestone are of 

 Waiarekan age, and that the limestone is Ototaran. The beds above the 

 limestone contain a distinctly Awamoan fauna, and, as both Hutton and 

 McKay believed that the Hutchinsonian and Awamoan were part and 

 parcel of the same series (and the evidence of the molluscan fauna in the. 

 Oamaru district supports this view), these fossiliferous beds (Otiake beds) 

 have been classed as Hutchinsonian-Awamoan. In the Oamaru district, 

 however, the occurrence of a brachiopod fauna fully justifies the separation 

 of the post-Ototaran rocks into two stages. 



The greensands between the Ngaparan coal-rocks and the limestone 

 in North Otago and South Canterbury will probably admit of subdivision 

 in the future. The fossils have hitherto been " lumped," but, judging 

 from McKay's report on the Waihao district, several lithological divisions 

 can be recognized ; and, as the rocks are very fossiliferous, careful col- 

 lecting and accurate determinations of fossils from each horizon would 

 probably enable a subdivision of the Waiarekan to be made, as has been 



