68 
WRIGHT : THE GENUS DIOSPYROS 
may be said to occur. Often, however, a leaf production 
may take place without a corresponding one of flowers, this 
being particularly noticeable in young trees having more 
than one period of leaf production a year. Again, flowers 
often appear on old woody twigs independent of leaf 
production, or recur in the same position year after year, 
sometimes in the axil of an old persistent leaf, and at other 
times in the old axil of a fallen leaf. In many trees of D. 
Ebenum and D. Toposia the majority of the flowers occur in 
the axils of new leaves, and therefore appear mainly at one 
time of the year, but such copious productions of flowers 
are invariably preceded and followed by periods of minor 
floral activity when the flowers appear without any definite 
relation to the leaves. 
It is therefore obvious that no generalizations can be 
made beyond stating that the greater part of the flower 
system usually makes its appearance immediately after a 
copious production of leaves. The importance of realizing 
the irregular nature of leaf and flower production is great, 
and one cannot lay too much stress on the fact that in the 
forests of Ceylon the species of Diospyros have not one fixed 
time of the year for flower production. In the Sabara- 
gamuwa districts there is not a month in the year when 
trees of D. insignis and D. hirsuta are absolutely flowerless, 
and the fact that trees of the same species growing alongside 
each other may possess either flower buds, mature flowers, 
ripe fruits, or no reproductive organs whatever during 
the same month, is sufficient to allow one to dispute any 
hypothesis based on the idea of a general seasonal 
periodicity. 
It may be further stated that many Diospyros trees 
probably remain flowerless for many years at a time, and the 
appearance of sexual organs cannot be correlated with the 
prevailing seasons. This was the opinion of Thwaites and 
Trimen, and most forest officers still firmly believe that the 
majority of Ceylon Diospyros trees flower but seldom. 
