~~ 
Cmar. XVI] MOVEMENTS OF THE LEAVES. 301 
(4:064 mm.) from the midrib. The margin now began to unfold, 
though the fly was left on the leaf; so that by the next morning 
(i.e. 48 hrs. from the time when the fly was first put on) the infolded 
edge had almost completely recovered its original position, being now 
*3 of an inch (7°62 mm.), instead of *16 of an inch, from the midrib. 
A trace of flexure was, however, still visible. 
Experiment 6.—A young and concave leaf was selected with its 
margins slightly and naturally incurved. Two rather large, oblong, 
rectangular pieces of roast meat were placed with their ends touching 
the infolded edge, and *46 of an inch (11°68 mm.) apart from one 
another. After 24 hrs. the margin was greatly and equally incurved 
(see fig. 16) throughout this space, and for a length of °12 or °13 of an 
inch (3°048 or 3°302 mm.) above and below each 
bit; so that the margin had been affected over a 
greater length between the two bits, owing to 
their conjoint action, than beyond them. The 
bits of meat were too large to be clasped by the 
margin, but they were tilted up, one of them so 
as to stand almost vertically. After 48 hrs. the 
margin was almost unfolded, and the bits had 
sunk down. When again examined after two 
days, the margin was quite unfolded, with the 
exception of the naturally inflected edge; and 
one of the bits of meat, the end of which had at 
first touched the edge, was now ‘067 of an inch 
(1:70 mm.) distant from it; so that this bit had 
been pushed thus far across the blade of the leaf. 
Experiment 7.—A bit of meat was placed close 
to the incurved edge of a rather young leaf, and 
after it had re-expanded, the bit was left lying 
"11 of an inch (2°795 mm.) from the edge. The 
distance from the edge to the midrib of the fully ue a: 
expanded leaf was *35 of an inch (8°89 mm.); pati ar bees 
so that the bit had been pushed inwards and across right prt ge es 
nearly one-third of its semi-diameter. against two square bits 
Experiment 8.—Cubes of sponge, soaked in a °f™eat. 
strong infusion of raw meat, were placed in close 
contact with the incurved edges of two leaves,—an older and younger 
one. The distance from the edges to the midribs was carefully 
measured. After 1 hr. 17 m. there appeared to be a trace of incur- 
vation. After 2 hrs. 17 m. both leaves were plainly inflected; the 
distance between the edges and midribs being now only half what it 
was at first. The incurvation increased slightly during the next 42 
Fic. 16. 
` hrs., but remained nearly the same for the next 17 hrs. 30 m. In 
35 hrs. from the time when the sponges were placed on the leaves, the 
margins were a little unfolded—to a greater degree in the younger than 
in the older leaf. The latter was not quite unfolded until the third 
day, and now both bits of sponge were left at the distance of *1 of an 
