and apatite occur in small quantities, as well as a little chlorite. 

 Forms a dyke on Mr. Henderson's farm, in rocks belonging to the 

 Hokanui System. 



Schistose Granite. 



Lower Bidler Gorge — Fine grained brownish-grey rocks, with 



the mica arranged, more or less regularly, into folije. S.G. 2-67 



to 2-76. Section : quartz, orthoclase, plagioclase, biotite, musco- 



vite. A large part of the quartz has been reduced to a fine 



pressure granulation and has flowed round the felspars which have 



retained their shape but have the angles rounded. The plagioclase 



is quite subordinate to the orthoclase. The mica is much bent. 



BLVANITB GROUP. 



(Quartz-felsite.) 



Microgranitic compounds of quartz and orthoclase, usually v 



porphyriti 

 hornblend 



crystals of quartz and often of orthoclase, mica, ( 

 blende in addition. 



Quail Island, Lyttelton Harbour — A finely granular, non-por- 

 phyritic white rock, stained yellow-brown in places. Section : 

 ■Granular, between microgranitic and microlitic, composed of 

 felspar microlites and laths from -006 to -008 in length with 

 ■quartz grains between them. 



Occurs as dykes. A doubtful Elvanite. Haast, Geol. Cant, 

 and Westland, p. 348 (Trachyte). 



Jfonnt William, near Westport — A pale grey rock consisting of 

 porphyritic crystals of quartz, felspar, and biotite in a small ground- 

 mass. S.G. 2'56. It contains fragments of other rocks. Section : 

 Ground-mass between microgranitic and microlitic formed by 

 colourless anisotropic grains, about -0006 in diameter, with low 

 polarization colours, small fragments of biotite and specks of 

 magnetite and pyrites in small quantity without any glassy base. 

 The porphyritic minerals are quartz, orthoclase, plagioclase and 

 tiotite. The quartzes are corroded and contain gas cavities, but I 

 5aw none with liquid and bubble ; the orthoclase has the same 

 kind of gas cavities as the quartz. These crystals go to -16 inch. 

 Given me by Dr. Gaze. I do not know its geological position. 



Lower Buller River — A blackish-grey, sub-vitreous rock with 

 distinct grains of quartz and crystals of felspar in a large ground- 

 mass. S.G. 2-69, It contains fragments of other rtx-ks. Section: 

 Ground-mass abundant between microgranitic and microlitic, 

 formed l)y colourless anisotropic grains from "OO-'J to -001 in diameer 

 and a few microlites of biotite in a small amount of glassy base. 

 The porphyritic minerals are (juartz, orthoclase, plagioclase and 

 biotite, from -06 to -08 in diameter. Magnetite is in scattered 



