LIVINGsTON—EsTABROOK : STOMATAL MOVEMENT IN PLANTs 21 
TABLE II—Continued 
Ejichhornia 
Upper leaf xsonged wer leaf surface 
Lo 
(9x stomata per sq. mm.) 
4 (18 mm.) 
Time ot obser- | _ 
nis Di i f op r Index “d Pisani Dimensions of open- aes of relativ 
ings, micra diffusiy: city ings, micra usive capacity 
Aug. 30 
3:00 p. m ————. _ —_—— —. 
6:30 p. m 9.0-11.7—-12.0 4.8—7.3-9.0 
15-75 13.53 
18.0-21.2—24.0 22.5-25.2-27.6 
Aug. 31 : 
12:30 a.m.] 4.5—7.5-12.0 1.8-5.6-9.0 
12.09 x Et.31 
15.0-19.8-24.0 18.0—-23.1-27.0 
5:30 a.m.| 4.5-9.2-11.4 3-9-6.7-12.0 
13.89 ~ 1237 
18.6-—21.0-24.0 20.I—22.7-27.0 
10:00 a.m.| 6.0—-II.I-15.9 6.9—10.1-12.0 
15.81 15.06 
16.5—22.8-27.0 19.5-22.6-26.4 
TABLE II—Continued 
Oenothera biennis 
Upper leaf surface (71 st Lower leaf surface (364 stomata 
Time of per sq. mm.) per sq. mm.) 
observation |~ RGreune Macrae Ween 
Dimensions of Index of relative Dimensions of Index of relative 
openings, micra diffusive capacity openings, micra diffusive capacity 
Sept. 7 ; 
I:00 p.m.| 3.6—-5.1-6.3 4.2-5.55-6.3 
7-11 7-74 
7-5-10.0-13.2 8.7—-10.9-18.0 
3:45 p.m.| 3.0—-4.3-6.0 0.0—-2.2—5.1 
6.42 4.23 
6.3-9.8-15.0 0,0—7.2—12.9 
6:20 p.m.| 2.4-3.3-4.8 0.0-1.6-3.6 
: 5.82 3.18 
7.8-10.4-12.0 0.0-6.5-12.9 
11:40 p. m. o Xo 0.0—1.6-3.0 
0.00 3 2.901 
0.0—-5.5—-12.0 
Sept. & 
5:40 a.m.| 1.8-3.8-5.1 0.0-2.3-4.2 
‘ 5.85 3.87 
6,.0—9.2--13.5 0.0-6.7-15.0 
I1I:00 a.m.) 3.0-4.4-6.0 1.8—2.9-4.5 
6.63 5-34 
6.0-10.I-15.0 
6.3-10.1-12.6 
