Vol. XI, No. 1.] The Defoliation of some Madras Trees. 21 
[N.S.] 
immediate evolution of the latter. In this case a mere 
retardation of functional activity and not complete removal is 
all that is necessary to induce the correlation to make itself 
away from the old leaves, which consequently are shed. Some- 
times an increased water-supply may induce the resting buds 
to develop in spite of the inhibitory effect of the functional 
old leaves. In that case the increased water-supply is sufficient 
for both the old leaves and the developing buds; and more- 
over, probably, the leaves on the tree being not too old yet, 
but quite active and healthy, and less laden with excreta, 
‘ Leaf-fall may result also from protracted wet weather......- 
Possibly the reduction of transpiration, if accompanied by 
strong turgor pressure, may result here in the ce. gene’ of 
ath.’’ 
the top downwards. Here the cause of the leaf-fall is probably 
physiological drought. When all the developing buds demand 
water, the first part of the tree to experience a shortage of 
ee 
1 Text-book of Botany. 
