268 W. R. BROWNE AND W. A. GREIG. 
It will be noticed that the relative proportions of light 
and dark constituents are very close to those of the quartz- 
monzonite. Although orthoclase and quartz are distinctly 
subordinate to plagioclase it is impossible to give definite 
figures for them, owing to the fineness of their grain making 
measurement difficult. Of the pyroxenes augite dominates 
over clino-hypersthene, and both minerals are represented 
in the groundmass. Olivine is present in about the same 
proportion asin the quartz-monzonite, and hornblende forms 
about one per cent. of the whole rock. The bulk of the 
plagioclase belongs to the first generation. 
The pyroxenes of the first generation have precisely the 
same characters and mutual relations as those of the quartz- 
monzonite. The plagioclase has the same range of com- 
position, but is perhaps slightly smaller in grainsize and 
less idiomorphic. The wonderful freedom from inclusions 
of the plagioclase of both rocks is hoteworthy. Biotite is 
smaller, but otherwise behaves as before. Iron ore occurs 
in two generations, the earlier often acting as nuclei for 
biotite and the later being a constituent of the interstitial 
groundmass. Apatite in tiny hair-like crystals is much 
more abundant than in the quartz-monzonite. Orthoclase 
and quartz are always subordinate, but no slide has been 
examined which does not contain both. The orthoclase is 
occasionally idiomorphic against quartz, and instead of 
being homogeneous is often filled with little vermicular 
inclusions of (?) quartz, the whole resembling not so much 
the ordinary granophyric intergrowth as that which is 
known as myrmekite. 
The order of consolidation appears to be somewhat as 
follows:—(1) olivine, (2) porphyritic pyroxene, (3) plagio- 
clase, (4) hornblende, (5) biotite, (6) apatite and the pyrox- 
ene and plagioclase of the groundmass, (7) orthoclase, (8) 
quartz. Magnetite crystallised partly before the porn 
pyroxene and partly along with the groundmass. 
