GIANT BAMBOOS. 
243 
A glance at the table shows that the temperature during 
the period of observation underwent only very slight and 
gradual changes, and the direction of these changes is 
generally speaking opposite to that of variations in the rate 
of growth. We may conclude that temperature has no 
material effect upon the observed results. 
An attempt was made to test the effect of light by shading 
a small halm by means of a cylindrical cover of tin. This 
experiment took place also on June 29 and 30, and is 
recorded in Table XIV. Halms Nos. 5 and 6 grew on the 
east side of the same clump as Nos. 1 and 2 ; they were of 
nearly equal height (No. 5 116 cm. and No. 6 103 cm. 
at 5.30 P.M. on June 28) and were less than half a metre 
apart. From 5.30 A.M. to 5.30 P.M. on June 30 No. 5 was 
covered with an opaque cylinder of tin, the base of which 
rested upon dry leaves heaped loosely round the base of the 
halm so as to allow as much ventilation as possible. The 
cover was removed every hour for some thirty seconds to 
allow of the growth being recorded. The table and curve 
seem to indicate that growth was very little affected by 
this treatment. 
And the same thing is shown still more clearly by another 
experiment, in this case upon a culm of Gigantochloa. A 
small shoot of this species (No. 13) was continuously covered 
up from 7.30 A.M. July 23 to 7.30 A.M. July 24. A shoot 
of equal height (No. 12) which was growing at nearly the 
same rate was used as a control. The experiment is recorded 
in Table XV. 
Table XV. 
Date. 
Growth in mm. 
1903. 
Time. 
No. 12. 
No. 13. 
July 21 
... 
5.30 P.M. 
10 
9-5 
22 
7.30 a.m. 
47 
... 46 
22 
5.30 P.M. 
9 
9-5 
23 
7.30 a.m. 
53 
... 48 
24 
7.30 „ 
68 
... (67) 
25 
7.30 „ 
78 
... 77 
26 
7.30 „ 
83 
... 79 
