288 The Philippine Journal of Science i9is 
Very conspicuous movements of the kind in question are shown 
by the young branches of Lagerstroemia speciosa (L) Pers., more 
commonly known as L. Flos-Reginae, a tree widespread in the 
Eastern Tropics wherever there are distinct wet and dry seasons, 
and commonly cultivated because of its gorgeous floral display. 
The tree is completely deciduous, at least under our conditions. 
Late in the dry season, but without waiting for the rains to 
begin, the buds begin to develop, springing from the axils of 
the leaves of the preceding season; no leaves are borne on the 
old wood. On each surviving branch of whatever order, the 
most distal bud assumes somewhat the character of an apical 
bud, those lower down giving rise to the season’s lateral 
branches; the distinction is not sharp, the terminal and lateral 
twigs shading from one to the other. The lowest of the latter 
are usually rudimentary. The season’s terminal shoot and the 
upper lateral branches may be expected to bear panicles of 
flowers, which the lower lateral branches as a rule do not. How- 
ever, the growth of the latter is most definitely and peculiarly 
limited. After the due number of nodes have been formed and 
have grown out of the bud, and while the growth of the inter- 
nodes and leaves is most rapid, growth in thickness stops 
abruptly at the last node which is to be permanent (for the 
S 2 ason) . Above this point, the shoot reaches a length of perhaps 
a centimeter, the leaves remain minute, and the exposed stem 
becomes hardly half a millimeter thick, while immediately below 
it the diameter may be four or five times as great. This stunted 
tip drops off before the growth below it is complete. Because 
of this blasting of the tip, the curve representing the growth of 
successive zones from the apex downward will be very peculiar 
if the chosen length of zones is very short. 
All growing branches, the rudimentary basal ones in so far as 
they grow, the lateral ones whose growth is terminated by the 
loss of the tip, and the flowering apical ones, are alike in exhibit- 
ing marked daily movements. At the height of the season’s 
growing period, these movements, carrying along the most of the 
foliage which has already developed, change the whole appear- 
ance of the tree. The petioles of the young leaves exhibit their 
own movements at the same time, but these have been reported 
upon sufficiently in the cases of other plants. 
A tree of Lagerstroemia grows by the path between my office 
and residence so that I habitually pass it in the early morning, 
at noon, and in the evening. The difference in appearance at 
different hours during its period of rapid growth was so striking 
that on April 13 I began a study of its behavior. All of the twigs 
