Park. — Marine Tertiaries of Otago and Canterbury. 545 



These are the analyses not of a single rock-specimen, but 

 of average samples selected from the total thickness of the 

 beds. The Weka Pass Stone contains a high proportion of 

 silica and a low proportion of calcium-carbonate, and is a very 

 poor sandy limestone. The Oamaru Stone is a high-class 

 limestone, remarkably low in alumina, iron-oxide, and silica. 



The Weka Pass Stone varies considerably in composition, 

 being more calcareous in the higher than the lower portion. 

 Near its junction with the Amuri limestone it is merely a 

 calcareous sandstone, as shown by the analysis of an average 

 sample selected about 2 ft. above the Amuri limestone : — 



Weka Pass Stone 



100-00 



The following analyses are interesting as showing that the 

 Amuri limestone becomes more siliceous as it approaches the 

 Weka Pass Stone : — 



100-00 



100-00 



The Weka Pass Stone seems to be entirely destitute of 

 molluscan fossils. I spent many hours searching acres of its 

 bare weathered surfaces, and only succeeded in rinding a few 

 broken echinoderm spines and a thin calcareous tube. The 

 ganger or foreman at the railway quarry near the 45-mile 

 post, in reply to my inquiries, informed me that he had never 

 seen a trace of fossils in the stone, of which thousands of tons 

 had been broken. 



35— Trans. 



