THE CEARA RUBBER TREE 153 



from the lower edge of each cut and then employing a 

 pricker ; the use of the pricker was, however, abandoned 

 during the expermient and the latex liberated sunply by 

 paring the edges of the cuts. The trees, which were 

 tapped fourteen times, yielded practically the same 

 quantity of latex from the first eleven tappings ; on the 

 twelfth day the flow of latex was rather sluggish and the 

 yield decreased very appreciably on the thirteenth and 

 foiurteenth days. Tapping was therefore abandoned 

 after the fourteenth day. 



The total yield of dry rubber was 2 lb., equal to a 

 yield of 10" 66 oz. from each tree in foiurteen daily tappings. 



(2) A second trial was made with four trees of various 

 sizes but having an average girth of 19^ in. The trees 

 were tapped ten times on alternate days, the herringbone 

 system being employed and the edges of the cuts being 

 reopened by paring. 



The total yield of dry rubber obtained was 15 oz., equal 

 to a yield of 3" 75 oz. per tree from ten tappings on alternate 

 days. 



(3) In a third experiment three Ceara trees approxi- 

 mately eight years old were used ; they were growing on 

 poor, stony soil, and had an average girth of 30 in. 

 Tapping was done by the half-herringbone system to a 

 height of 4| ft. and was continued every alternate day 

 for ten weeks, the parer and pricker being used. 



The total yield of dry rubber was 57 oz., equal to 

 19 oz. per tree in ten weeks. 



The wound response was stated to have been good 

 throughout the experiment, and, except in the case of 

 one tree which was tapped a little too deeply, new bark 

 formed rapidly at the conclusion of the experiment. 



(4) A further experiment was conducted on a planta- 

 tion of Ceara trees at Entebbe. Twenty trees approxi- 

 mately two and three-quarter years old were employed ; 

 the average girth of the trees was 19 in. at 3 ft. from 

 the ground, the largest being 26 in. and the smallest 

 16 in. The tapping was done by the half-herringbone 

 system, using half the bark to a height of 3^ ft., and was 

 repeated every alternate evening between 5.30 and 

 6.30 p.m. for one month, each tree being tapped fifteen 

 times by paring and pricking. 



The total yield of dry rubber was 2 lb. oh oz., of which 



