BY W. G. WOOLNOUGH. 799 



Analysis BY L. A. Cotton, B.A., B.Sc. 



Per cent. Molecular proportion 



SiOa 73-54 ... 1226 



AI2O3 10-95 ... 108 



Fe^Og 1-08 ... 7 



FeO ... 4-39 ... 61 



MgO 0-08 ... 2 



CaO 1-68 ... 30 



Na^O 2-79 ... 45 



K2O 4-80 ... 51 



H2O + 0-21 .. — 



H,0- 0-08 ... — 



TiOa 0-60 .. 8 



Total 100-20 



Per cent. 



Norm. Quartz 33"60 



Orthoclase 2S-36 



Albite 23-58 



Anorthite 3-34 



Diopside 443 



Hypersthene 3-93 



Magnetite 1-62 



Ilmenite 1-22 



Sub-Rang 

 Tehamose. 



100-08 



In spite of the very wide differences in the analyses of the 

 grano-diorite and the dacite, I feel con6dent, from field-evidence, 

 that the two are genetically related. The differences probably 

 express magmatic differentiation. 



Series of sj^ecimens taken from the contact between lower 

 limestone-hed and grano-diorite. 



The numbers read consecutively from soutli to north. There 

 is a long gap between the lust distinct outcrop of unsilicified 

 marble, and the first of the contact-series(No.l), which is some- 



