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FETCH ; 
curves for 1913, but these are, at least in part, explainable 
by the irregularity in the leaf-fall which occurred in that 
year. How long before the leaf-fall the growth in girth 
eeases depends apparently upon the individual tree. It may 
be three months, as in tree No. 3, or only one or two weeks, 
as in tree No. 15. In general the increase in girth begins again 
from one to three weeks after the leaves are fully formed. 
Brown states that, in Finns Strohns, growth in thickness 
begins before growth in length in each year. His data were 
obtained from determinations of cambial activity, and are 
therefore more aecurate than those of the present case, but 
he quotes Christison’s results, which were obtained from 
bark measurements, as agreeing with his own. The measure- 
ments on Hevea indicate that in this species growth in length 
occurs before the stem increases in thickness by any amount 
perceptible by external measurements at a height of 6 feet. 
In Ceylon increase in length in the stems and branches 
of Hevea brasiliensis proceeds by sudden and brief bursts. A 
green shoot, varying in length from about 3 inches on the 
lower branches to about 2 feet in the ease of a leader, is 
produced, bearing rudimentary leaves ; the latter develop 
to their full size, remain limp for a few days, and then become 
rigid and assume their normal position. The leaves are 
born chiefly towards the apex of the new shoot, and the 
petioles of the lower are elongated, so that the leaves form, 
more or less, a rosette. The whole process occupies from two 
to four weeks at the elevation of Peradeniya. 
At various times during the year other outbursts of new 
shoots occur. Indeed, it is scarcely possible to look at a 
Hevea plantation of about ten years’ standing at any time 
without seeing new shoots on some of the trees. The pale 
green of the new shoots contrasts strongly with the darker 
older foliage, and consequently the phenomenon is one well- 
known to all rubber planters. But opinions differ widely 
as to the number of times it occurs during the year, as many 
as six having been claimed. 
Observations on the measured trees at Peradeniya have 
shown that at this elevation, in addition to the first re-clothing 
of the tree, there may be two main periods of production 
