So Keeble . — The Hanging Foliage of 
That bright sunlight brings about a depression was 
also shown in another way. Six seedling plants of Brownea 
grandiceps , at similar stages of development, were selected 
from a batch. Of these, two were placed in the open, fully 
exposed to the direct rays of the sun, the others were left in 
a room. When so placed there was nothing in the disposi- 
tion of the leaves of the former to distinguish them from 
those of the plants which remained in the room. At the end 
of the first day of exposure it was found, as in the preceding 
case, that the leaves of the two plants in the open, made far 
larger angles with the horizontal — were much more depressed 
— than the leaves of those plants which were in the room. 
At the end of five days the difference between the two sets 
was most pronounced — all the leaves of the sun-exposed plants 
hung vertically down, whilst those of the plants in the room 
stood out more or less horizontally (cf. Fig. i with Fig. 2). 
Although the effect of exposure to the sun was so great, the 
daily periodicity of the movement was not destroyed ; only 
the upward movement was greatly reduced. The same plant, 
when brought back into the diffuse light of the room, gradu- 
ally recovered itself, so to speak, so that after several days 
the leaves raised themselves so as to stand horizontally, and 
once more performed their periodic movement in a way 
similar to that which obtained before exposure. 
In the case of Anther stia nobilis it was not possible to 
directly measure the angles which the leaves made at various 
times with the vertical, although, as already stated, the general 
course of the movement can readily be followed without special 
arrangement. It was possible, however, by a rough method, 
not only to demonstrate the general course of movement 
of the leaflets of this plant during the day, but also to 
observe the relation that movement bears to the amount of 
insolation. 
Fine beeswaxed threads were passed between opposite 
pairs of leaflets through holes in the basal parts of their 
laminae, close to the junction of lamina and petiole. The 
holes were large enough not to cause friction between the 
