THE AFRICAN RUBBER TREE 



177 



It is interesting to note that in these trials the native 

 system of tapping gave the best results. The yield of 

 rubber per tree obtained by this method was only slightly 

 below the highest yield furnished by the other systems 

 employed, and the cost of collection was considerably 

 less. All the yields were, however, very small. 



II. Durmg 1910-11 an experiment on a larger scale was 

 made at Aburi, in order to determine (1) the best time to 

 tap Funtumia trees ; (2) the comparative yield from trees 

 of different girth ; and (3) the average yield per tree at the 

 first and subsequent tappings. 425 trees, which were just 

 over ten years old at the beginning of the experiment, were 

 divided, accordmg to girth, into five groups as follows : 



