IN CEYLON. 
429 
periodicity of a prominent tree of this species from 1900 to 
1905 has been given in the section dealing with decidnons 
species indigenous to Ceylon and India. It is by no means 
rare to find that a particular tree which produces a complete 
set of new leaves after the leafless stage produces small 
quantities of leaves during other months of the year : 
such activities may be observed in trees of Swietenia Maho- 
gani, Chloroxylon Swietenia, Terminalia belerica, Bassia 
longif olia, and others. 
It is also not unusual to find that every alternate year the 
production of new leaves on certain trees is very copious, 
this being particularly striking in evergreen trees of Garcinia 
Mangosteen, Durio zibethinus, and. Mangifera indica. 
Abnwmal Defoliation and Foliar Renewal. 
In certain cases the abnormal production or fall of leaves 
is due to a condition of vigour, undue exposure to wind, or 
the attacks of animals. Trees of Acacia Suma and Canarium 
zeylanicum, which have lacked the vigour of other speci¬ 
mens of the same species, have been observed to take a 
much longer period to renew their foliage. The periodici¬ 
ties of such specimens are usually variable and unreliable. 
The effect of the strong winds during certain months of the 
year can be observed on exposed trees of Mangifera indica, 
Tecoma stans, and others, these trees becoming more nearly 
leafless than other specimens of the same species. 
I have also had an opportunity of recording the change of 
periodicity due to cutting away the upper parts of trees of 
Mangifera indica and Terminalia Catappa. A tree of Mangi¬ 
fera indica which normally produced its leaves in February 
and March was lopped in May after the full set of foliage 
had been established ; the tree produced a large quantity of 
leaves during July to September of the same year, but in the 
following year the leaf production due in February and 
March was not observed. A tree of Terminalia Catappa 
was similarly treated in May, with the result that there 
was a large output of new leaves in July and August, 
8(9)05 (10) 
