THE HEVEA RUBBER TREE IX THE AMAZON VALLEY 
63 
in diameter. Probably the trees, especially the last one, were older 
than they were said to be, but there is no doubt that the tree grows 
rapidly. The wood is soft and light. 
Fig. 14.— A tree of Sapium (on the right) beside a Para rubber tree in an estrada at Paraiso, on the 
Madeira River 
Little is known of the quantity of itapuru rubber which exists in 
the Amazon, but it is probably not great. The tree seems to be 
most common on flooded land, where it thrives much better than the 
Para rubber tree. 
On account of the rapid growth of this tree and of the good qual- 
ity of rubber which it produces, it is deserving of experimental trials. 
