Tropical Forests 
to the exhausted and languid explorer unless he happens 
to be a botanist. Then of course he is interested and 
busy from morning to night, for a lifetime would be in- 
sufficient to understand and appreciate all the problems 
that perplex him. 
The characteristic products of such jungles are not 
very many. The rubber vines of Africa (Landolphia sp.) 
and the various rubber trees and creepers of South 
America, the guttapercha and rubber of the East Indies 
are by far the most important economically, 
The peculiar white juice or latex which exudes from 
the stems of these Apocynacez, Asclepiadacez, Moracez, 
&c., contains caoutchouc, resins, and other ingredients, 
This latex is of great importance to the plant. It is 
poisonous, and is so arranged in a network of internal 
tubes and channels that any cut or wound will neces- 
sarily result in a plentiful flow of latex to the injured 
place. 
Trees denuded of rubber by the natives were noticed 
by Bates to have been stripped of their leaves by 
the parasol ant and probably destroyed. Upon any 
wound the rubber will coagulate, and its elasticity and 
poisonous and resinous characteristics make it invalu- 
able to cover over the scars and to prevent insects, 
fungi, or bacteria from entering. If one disregards a 
few exceptional cases, rubber and guttapercha plants 
are confined to and invariably found in wet-jungles. 
The valuable Hevea of Brazil seems to belong to the 
great stretch of forest country which is regularly inun- 
dated by the annual flood of the Amazon, and which 
is specially remarkable for its extraordinary ant-plants. 
In Africa it is the Landolphias which form the main 
supply. 
In both Brazil and Africa the rubber is chiefly a 
wild jungle product, obtained by native collectors who 
are utterly unable to foresee or provide against the 
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