428 BOTANICAL GAZETTE [JUNE 
TABLE I—Continued 
- Transpiration | Transpiration Percentage 
Hour at which of healthy of diseased of water 
No. Date experiment leaves in gm. leaves in gm. | transpired by 
. began per hr. per per hr. per diseased 
sq. cm. sq. cm. leaves 
IgII 
ye EEaPe Se cara: July 26 00 0.0025 0.0022 88.0 
oa 27 10:03 A.M 0.0052 0.0043 82:7 
BUS iad One 27 2:14 P.M 0.0024 0.0019 79.2 
G2 ee es a7 3:30 P.M 0.0029 0.0016 62.1 
TABLE II 
TRANSPIRATION OF HEALTHY AND DISEASED BEN DAVIS LEAVES 
Transpiration | Transpiration Percentage 
eo at which of healthy of diseased of water 
No. Date riment leaves in gm. leaves in seg transpired by 
hewks per hr. per per hr. diseased 
. cm. sq. ae leaves 
Igi2 
OOo oa. s July 11 9:40 A.M. O.OIOI 0.009 89.1 
Cr Lt 10:27 A.M. O.OIOI 0.0056 Ss.4 
a ees ok It 2:24 P.M. 0.0128 0.0073 57-9 
ee II 3:40 P.M. 0.0004 0.0048 51.0 
Otros 19 9:50 A.M 0.0065 ©.0032 49.2 
Bes aks 19 8:40 A.M 0.0032 0.0026 81.25 
Oro se 19 12:40 P.M 0.0065 0.00305 46.9 
Sy get Lane 19 I:50 P.M 0.0043 0.00406 04.4 
eee ee es 20 0:54 A.M 0.0041 0.0025 61.0 
Oe 20 8:45 AM 0.0042 0.0020 47.6 
7 a Ba lg ana 20 1:50 P.M 0.0031 0.0037 119.3 
Pea, 29 2:20 P.M, 0.00675 0.00597 88.4 
(2 a deena es 29 3:25 P.M. 0.00013 0.0066 72.5 
A Re ee rae 30 9:20 A.M. 0.0053 0.0041 77.2 
fe. Ce Senn 30 8:20 A.M. 0.00574 0.00409 W1.2 
FR cg a get 30 2:44 P.M. 0.0100 ©.00442 44.2 
Y Ae fe arate Gaae® 30 2:45 P.M. 0.0061 0.0045 73.8 
yy Peo ee Aug. 22 10:44 A.M 0.0065 0.0045 2 
We Se, 22 3:08 P.M 0.00638 0.0042 65.8 
763 StS Ae a gee 22 4:20 P.M 0.0028 0.0034 E214 
Ba. 9:28 AM 0.0044 0.0034 qT 3 
IQII 
ty Ng a Ne July 22 3:45 P.M 0.00243 0.0017 68.7 
ee eg a 24 2:46 P.M ©.0075 2.0039 52.0 
ss A Ne 24. 2:57 P.M 0.0067 0.0023 34.3 
ae 25 II:00 A.M 0.0039 0.0061 156.4 
Oye ose. 25 3:45 P.M 0.0079 0.0046 58.2 
leaves comes out very nearly the same in each variety of apple 
studied, 78.3 for the York and 74.2 for the Ben Davis. 
The ratios show certain differences if they are grouped accord- 
ing to periods covering different stages in the development of the 
disease. The first, from July 1 to 15, is a stage in which the fungus 
is still immature. At that time none of the peridia have broken 
