560 The American Naturalist. [July, 
clearly due to the transpiration of hot water. (Subsequent ex- 
periments showed that it is very easy to push this wilting be- 
yond the power of the plant to recover). 4:15 p. m. The 
plant stands up well. There is no trace of wilt. March 23, 
11 a.m. No sign of wilt. Noon. The lowest five leaves 
show distinct signs of wilt at the tip of the blade. None of 
the upper leaves show any trace of it. 12:25 p.m. The wilt- 
ing is worse but is still confined to the lower leaves. It is 
very decided on the lowest one which is exposed to the bright 
sun. The tender apical leaves are turgid, as well as those in 
the mid part of the stem. 1:20p.m. The leaf next to the 
lowest one begins to crisp. 3:00 p.m. Blade of lowest leaf 
but one is now crisp, and the blades of the other four are dry- 
ing out at the apex and on the margins and between the 
larger veins. 4:30 p*m. No change. The bulk of the foliage 
stands up well, including all of the upper leaves March 
25, 1:20 p.m. The lower leaves of this plant are dried out to 
a greater extent than are those of No. 11, but the major part 
of the foliage is normal and the tips of both vines are notice- 
ably turgid. The drying out of the parenchyma between the 
veins is also to be seen in the affected leaves of this vine, the 
larger veins and a narrow border of theleaf parenchymaremain- 
inga brightgreen. 5:40p.m. Thevinestandsup well. Itis 
three days and four hours since the stem was boiled. March 
26, 3:00 p.m. The vine begins to show symptoms of collaps- 
ing. All of the petioles are turgid, but the blade of the low- 
est leaf is nearly dry, that of the next up is wholly dry; those 
of the next three above are crisp at the apex and on the mar 
gins (one-fifth to one-third the surface); the three next up 
show a trace of drying on their margins, and in all the rest 
there is a faint suggestion of loss of turgor. March 27, 2:00 p. 
m. All of the leaves on this vine are now crisp-dry except 
three at the top which are flabby. The stem and the petioles 
are still turgid. March 28, 1:30 p.m. The upper three leaves 
are still flabby, and all of the petioles are still rigid except the 
tips of some of the lower ones which begin to droop. 
This vine gives results confirmatory of the preceding. For 
more than three days the plant was able to draw all of the 
