^6 



TROPIfAI. Wir.D I. IFF, IN BRITISH GUIAXA 



FIG. 11. MAP OF THE GENERAL FIELD OF WORK IN BARTICA DISTRICT 



auriferous, carrying about thirty-six grains of gold to the 

 ton. Meagre as is this percentage, it is exciting to a passing 

 naturahst and tempts one always to pick up a bit of the 



