57 



EXPLANATION OF PLATES. 



Plate I. 

 Fig. 1. Microcline from porphyritic granite, with rim of quartz 

 granules in graphic intergrowth with the felspar 



,, 2. Chequer albite from soda aplite, Port Elliot (x23). 



,, 3. Quartz in adamellite porphyry showing ''nibbled" out- 

 line, surrounded by a ring of optically continuous 

 quartz granules (xl6^). 



,, 4. Uralitic dolerite from dyke on landward side of Rosetta 

 Head. Ordinary light (xl5). 



,, 5. Mica schist with porphyroblast of chlorite cutting across 

 the schistosity. Cliff section, Rosetta Head. Note 

 quartz inclusions carrying schistosity through the 

 chlorite. Ordinary light (x33). 



,, 6. Albitic hornfels from near contact of albite syenite, 

 Rosetta Head. Portion of a chlorite veinlet is visible 

 (x44). 



Plate II. 



Fig. 1. Mica schist with "knots" of sericite, cliff section, Rosetta 

 Head. Ordinary light (xl6^). 

 ,, 2. Andalusite porphyroblast in mica schist, Rosetta Head. 

 Note the biotite folia partly pushed aside and partly 

 cut across by the andalusite. Ordinary light (xll). 



Plate III. 

 Fig. 1. Adamellite porphyry from Granite Island, showing a 

 simply-twinned, well-rounded phenocryst of microcline. 

 ,, 2. Boulder of porphyritic granite on Granite Island showing 

 the characteristic weathering. 



Plate IV. 

 Fig. 1. Contorted schists at contact with albite syenite, Rosetta 

 Head. 

 ,, 2. R-osetta Head from King Point. The seaAvard side of 

 the headland is of granite and syenite ; the sloping 

 ground at the back is composed of schists, which also 

 form the outcrops close to the sea level in the fore- 

 ground and middle distance. The low cliffs are of 

 Permo-Carboniferous glacial deposits. 



