Pirate IV. Upper figure. Young leaves of Hevea 
viridis showing their lustrous surfaces, near ‘Tay- 
asi, Vaupés River, Vaupés. 
Lower figure. Trunk of Hevea viridis, near Tay- 
asi, Vaupés River, Vaupés. 
Pirate V. Upper figure. Hevea viridis var. toxico- 
dendroides at the type locality, Cerro Chiribiquete, 
Vaupés. This illustrates the erect habit of the 
plant. 
Lower figure. Cretaceous sandstone ridges of the 
upper Apaporis River basin, Vaupés, where Hevea 
viridis var. toxicodendroides abounds on the xero- 
phytic summits. 
Piate VI. Upper figure. Seeds of Hevea viridis 
from lower Vaupés River, Vaupés. 
Lower figure. Hevea viridis var. toxicodendroides 
with fruit. Cerro Chiribiquete, Apaporis River, 
Vaupés. 
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