412 BOTANICAL GAZETTE [JUNE 
tissue from loss of water. Even in summer and especially in fall, 
when the sap flow decreases, the tender embryonic interior of the 
bud must be protected from too great transpiration. Also in winter 
this function is not interrupted, for then the cold wind can bring 
into play its desiccating action. To prevent loss of water, cork 
layers are formed, or in place of these felty hairs may be produced. 
A third method. consists in the excretion of resin. If, under con- 
stant temperature, the scales were removed from an oak bud, it 
soon died, even though there was a moderate amount of moisture 
present. The inner bud-scales dried out and perished, as well 
as the embryonic tissues. The young leaves of a beech bud so 
deprived of scales persisted much longer than did those of the 
European oak; which he thinks was because the former were hairy 
while the latter were not. Buds of horsechestnut proceeded to 
develop in spite of the removal of the scales, probably, he thinks, 
because of the thick wool among the young parts. Buds of Abies 
pinsapo, whose pitch had been removed by carbon bisulfid, dried 
out in a very short time. These experiments were all performed 
on twigs cut from the trees and placed in water. 
In 1895 Kny?° published a paper dealing with the transpira- 
tion and absorption of water by buds and twigs in winter. He 
cites WIESNER and PACHER as having shown that horsechestnut 
loses water from twigs in winter, and also Hartic as having shown 
that many trees do the same. Experiments are given to show that 
in general not so much water is absorbed by these parts in saturated 
atmosphere as may be given off at an ordinary degree of saturation. 
In 1895 some determinations of the amount of water lost by 
twigs with buds attached were made by the Cornell Experiment 
Station.?”7_ The experiments lasted three days, beginning April 7. 
The twigs were sealed at the cut end and kept in an open shed. 
The percentage of loss ranged from 2 to 10%, with an average of 
5-4%- 
In 1875 WIESNER and PacHER?® found that twigs of horsechest- 
26 Kny, L., Ueber die Aufnahme tropfbarfliissigen Wassers durch winterlich- 
entlaubte Cutis von Holzgewachsen. Ber. Deutsch. Bot. Gesell. 13:361- 1895- 
27 BaILEy, L. H., Cornell University Experiment Station Rep. 1896: 4. 
28 WIESNER u. PacHER, Ueber die Transpiration entlaubter Zweige und des 
Stammes der ete ge Bot. Zeitschr. No. 5. p. 9. 1875. 
