Park. — The Bock-phosj^hates of Otago. 395 



ditions, and show that the sediments forming this sandstone 

 accumulated near the shore-line of a shallow sea, with shoals 

 of rock and stretches of clear sand. On the other hand, the 

 mineral glauconite is known to he formed by filling or re- 

 placing organic bodies, generally Foraminifera, by a process of 

 slow replacement, molecule by molecule, under conditions 

 which would require the absence of strong sea-currents and a 

 coast-line free from the encroachment of fluviatile deposits. 



(b.) Limestone. — This rock has its greatest development at 

 Millburn quarry, where there is a face exposed showing a 

 thickness of about 65 ft. The total thickness from the highest 

 pinnacle down to the upper surface of the glauconitic sand- 

 stone is probably 80 ft. 



In the phosphate-quarry at Kiln Point only the lower hori- 

 zon of the limestone is exposed ; while at Millburn both the 

 lower and upper horizons are seen. The lower horizon, com- 

 prising, perhaps, a thickness of 25 ft., is speckled with glau- 

 conite, and, being sandy or arenaceous, forms an inferior 

 limestone. The upper horizon is dull-grey in colour, almost 

 free from glauconite, and of purer quality than the lower. It 

 is often flaky and splintery, and, being fine-grained and earthy 

 in some places, bears a strong superficial resemblance to the 

 Amuri limestone of northern Canterbury, with which, how- 

 ever, it has no connection. 



In the spoil-heap of the quarry at Millburn were found the 

 jaw and teeth of a Zeucjlodont whale, Pecten hochstetteri, 

 Meoma crawfordi, a Waldheimia. a branching net coral, and 

 a solid coral. 



This rock is the horizontal or time-equivalent of the 

 Oamaru stone, which is the closing member of the New Zea- 

 land Lower Tertiary coal-bearing formation. It is the most 

 characteristic and persistent member of that formation, and 

 is seldom or never absent where coal is found. It occurs 

 throughout both Islands, and is everywhere easily distin- 

 guished. In places, through the scarcity of lime, it is little 

 more than a calcareous sandstone or impure limestone ; while 

 in other places it is very pure and highly crystalline in 

 structure. 



In different districts it has received the name of the 

 locality in which it is found. Thus, in Southland it is called 

 the " Winton limestone"; in Bruce countrv, the "Milton 

 or Millburn limestone " ; in North Otago, " Oamaru stone" ; 

 in South Canterbury, the " Waihao limestone " ; in North 

 Canterbury, " Weka Pass stone" ; at Mokau, " Mokau lime- 

 stone" ; in the King-country, " Te Kuiti limestone"; at 

 Raglan, "Raglan limestone"; in Waikato, " Taupiri lime- 

 stone"; while at Whangarei, Hikurangi, Kawakawa, and 

 Waipu it has received these names respectively ; and so also 



