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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 24, 



Fig. 1. — Shetch Map of the tJeology of British Quiana. 

 Scale 104 miles to 1 inch. 



Alluvium ^^ 



Sandstone formation . . . |rgvg 

 Metamorphic Series . . . If^Efj 

 Quartz -porphyry |^^ 



Granite and Syenite 

 G-reenstone dykes . . . 

 Quartz veins 



