52 BOTANICAL GAZETTE [anvary 
for a period not to exceed 9 days. The longer the steamed portion a 
of the stem is, the sooner the leaves above lose their turgidity 
wither, and dry. This is conspicuous in the cases of the plants 
in experiments 6—S (1908), 56—S (1909), 62—S (1909), 27S 
(1910), 74—S (1910), 101—S (1910), rog—S (1910), and 137—S 
(1910), as comparéd with the others in which shorter sections were 
killed, as in r4—S (1908), s0—S (1908), 5 —S (1909), 24—S (1909); 
63—S (1910), and especially 133—S (1910) and 137—S (1910). 
When plants of Cyperus have a portion of the stems steamed, 
the leaves above show no immediate effect. After some time, 
depending upon the length of the stretch heated, the involucral 
rays usually begin to droop, closing more or less about the stem. 
rolled inward, and dryness supervenes. In some cases discolora- 
tion follows the treatment, the leaves becoming spotted. This 
discoloration usually takes place at the tips first, but may occur 
also at the bases of the rays. I have noticed that this discolorati n 
is dependent upon the length of.the stem killed. When very 5 
portions are steamed, the leaves usually wither and dry wit 
discoloring, behaving like those on cut stems in this respect. V 
on the other hand, longer portions are heated, discoloration usually 
follows. This fact seems to me to indicate, as Drxon maintai 
that poisonous substances may be carried to the leaves from 
killed portion. 
In comparing the above results with those of experiments © 
Gramineae as described by RosHarpt, in which ro to 20 cm. of ¥ : 
halms were steamed, Cyperus appears to be able to retain the t 
ity of its leaves after such treatment about as long as any of 
grasses. The leaves finally droop at the bases, so that the wh 
involucre closes about the stem like the ribs of a closed umb 
This is always the first sign that the plant has suffered from ™ 
treatment; yellowing of the tips and bases may also occur; ant 
finally the leaves dry out after, in some cases, assuming a 4r0op 
position. In some instances the edges of the drying leaf becom 
inrolled. Perhaps the initial drooping of the leaves or loss 9 ‘ 
turgidity may be due to some toxic action initiated by the 1 
ment. Leaves on cut stems of Cyperus lose their turgidity ‘ 
