32 TROPICAL NATURE, AND OTHER ESSAYS. 



caused by accident or decay, but repeated examination 

 shows it be due to the natural growth of the tree. The 

 accompanying outline sections of one of these trees that 

 was cut down, exhibits its character. It was a noble 



Sections of trunk of a Bornean Forest-tree. 



1. Section at seven feet from the ground. 



2. 3. Sections much higher up. 



forest-tree, more than 200 feet high, but rather slender 

 in proportion, and it was by no means an extreme 

 example of its class. This peculiar form is probably 

 produced by the downward growth of aerial roots, like 

 some New Zealand trees whose growth has been traced, 

 and of whose different stages drawings may be seen at 

 the Library of the Linnean Society. These commence 

 their existence as parasitical climbers which take root in 

 the fork of some forest-tree and send down aerial roots 

 which clasp round the stem that upholds them. As 

 these roots increase in size and grow together laterally 

 they cause the death of their foster-parent. The climber 

 then grows rapidly, sending out large branches above 

 and spreading roots below, and as the supporting tree 

 decays away the aerial roots grow together and form a 



