Palaeozoic Geolo(jy of Victoria. 69 



■3. SerpentinouE Grit, Upper Cambrian, Dolodrook Eiver. 



4. Rhyolite Tuff, Upper Palaeozoic, Lake Karng, Mt. Wellington. 



5. Melaphyre, Upper Palaeozoic, Wallaby Creek, Welliiifftxi District. 



6. Porphyroid, Lower Devonian, Ironstone Creek, Nowa Nowa. 



7. Porphyroid, Lower Devonian, Boggy Creek, Nowa Nowa. 



8. Altered Andegite. Lower Devonian, Boggy Creek, Nowa Nowa. 



9. Tra<;liytic Andesite, Lower Dei\-oniain, Nowa Nowa. 



10. Quartz-Porphyrite, Lower Devonian, Tara Range. 



11. Quartz-Ceratophyre, Lower Devonian, Nowa Nowa. 



12. Quartz-Ceratophyre, Lower Devonian, Nowa Nowa. 



Description of Photomicrographs. 



iFig. 1. — ^Sertientinized peridotite, showing some unalltered olivine. Pre- 

 Upper-Cambrian, Serpentine area, Mt. Wellington District. 



Slide No. 182. Ordinary light x 40. 



.Fig. 2. — Serpentinous grit, showing much calcite and altered basic 

 igneous fragments. Upper Cambrian. Dolodrook R., Loc. B. 



Slide No. 39. Ordinary light x 40. 



Fig^. 3. — Serpentinous grit, showing much caloite, one example twinned, 

 also felspar and pyroxene fragments much altered. Upper Cam- 

 briaji, Loc. B. 



No. 41, Crossed Nicols x 40. 



Fig. 4. — Rhyolite tuff, showing irregular tuib? structures set in felsitic 

 ground-ma*6. Upper Palaeozoic, Lake Karng, Mt. Wellington. 



No. 111. Crov-sed Nicols x 40. 



Fig. 5. — Melaphyre, s^howing abundant laths of triclinic felspar, probably 

 ol"'gocla.se, with .lome chlorite and magnetite. Upper PalaeoZv>ic, 

 Wallaby Creek, Mt. Wellington District. 



No. 177. Ordi'-iary light x 40- 



Fig. 6. — Porphyroid. Sciiistoee structure indicated by lines of sericite ; 

 some tricline felspar fragments are ."et in a schistose felsitic 

 base. Lower Devonian. Ironstone Creek, Nowa-Nowa, 



No. 27. Crossed Nicols x 40. 



Fig. 7. — Porphyroid. Schistose structure indicated by lines of sericite; 

 felspar fragments small and less abundant. Lower Devonian, 

 Boggy Creek. 



No. 2. Crossed Nicols x 40. 



:Fig. 8. — Altered Andesitp. Phenocrysts of triclinic felspar of stout 

 habit and chloritized ferro-magnesian minerals in a micrccrys- 

 talline ground-mass. Lower Devonian, Bc^gy Creek. 



No. 11, Ordinary light y 40. 



Fig. 9. — Trachytic-Andesite, .showing abundant triclinic fel.spars of 2 

 generations and central felspar, showing secondary alteration. 

 Lower Devonian, Boggy Creek. 



No. 12. Ordinary light x 40. 



"Fig. 10. — Quartz-porphyrite, showing eimbayed quartz phenocryst. Lower 

 Devonian. Tara Range. 



No. 105. Crossed Nicols x 40. 



".Fig. 11. — Quartz-oeratophyre, showing triclinic fel«=T)ar phenocrysts, prob- 

 ably andesine. Lower Devonian, Nowa-Nowa. 



No. 68. Crossed Nicols x 40. 

 Tig. 12. — Quartz ceratophyre (features as in Fig. 11). 



No. 68. Croesed Nicols y 40. 



