xin, c, 6 Brown and Trelease: Shrinkage and Elongation 355 
Table I . — Measurements of shoots of plant 1 of Oestrum nocturnum at 
various hours during the day and night. 
Tem- 
Evapo- 
ration 
per 
hour. 
Measurements of shoots. 
Time. 
pera- 
ture. 
Illumination. 
Shoot 
1. 
Shoot 
2. 
Shoot 
3. 
Shoot 
4. 
Condition of shoots. 
i 
p. m. 
12.30 
cc. 
1. 32 
cm. 
9. 40 
cm. 
7. 60 
cm. 
12. 50 
cm. 
7.60 
Much wilted. 
1.30 
1.38 
9. 50 
7. 65 
12.60 
7.65 
Do. 
2.30 
1.20 
9. 60 
7.65 
12.60 
7. 65 
4.00 
0. 84 
9. 50 
7.65 
12. 65 
7. 70 
Slightly wilted. 
6.00 
27 
0. 90 
9. 65 
7.75 
12.70 
7. 76 
Straight. 
8.30 
26 
0. 30 
Dark -- 
9. 75 
7. 86 
12. 85 
7.80 
Curved upward. 
a. m. 
7. 00 
25 
0. 18 
10. 25 
8.25 
13.30 
8.26 
Do. 
8. 00_ .. 
28 
0. 58 
10.20 
8.26 
13.30 
8.30 
Slightly curved 
9.00 
29 
1.34 
do 
10. 10 
8. 10 
13. 16 
8.20 
downward. 
Very visibly wilted. 
10. 00 
31 
1. 63 
- ... .do . 
10. 00 
8. 10 
13.05 
8.15 
Much wilted. 
11.00 
29 
1.63 
do 
10.00 
8. 10 
13. 10 
8. 15 
Do. 
12 noon__ 
30 
1. 44 
Diffused light 
10.05 
8. 15 
13. 10 
8. 20 
Do. 
p. m. 
1.00 
33 
2.30 
Shade 
10.05 
8. 15 
13. 15 
8.20 
Less wilted. 
2.00 
33 
2. 40 
10. 10 
8.15 
13.20 
8. 20 
Slightly wilted. 
Do. 
3. 00 
32 
2.11 
do 
10. 10 
8.20 
13.20 
8. 25 
4.00 
32 
2. 21 
. .do - 
10. 10 
8.20 
13.25 
8.25 
Very slightly wilted. 1 
5. 00 
30 
2.21 
do 
10. 10 
8.25 
13.25 
8. 25 
Do. 
6. 00 
27 
1.34 
Dusk 
10. 15 
8.26 
13.25 
8.30 
Straight. 
8. 00 
27 
0.72 
Dark 
10. 20 
8.25 
13.30 
8. 30 
Curved upward. 
noon, when the first measurement was made, the shoots were very 
much wilted, as they were also at the time of the second measure- 
ment. Following this they became less wilted and were straight 
by 6 o’clock, and at 8.30 in the evening they were curved upward. 
This whole period was one during which the shoots were ap- 
parently recovering from wilting, and in doing so they showed 
an elongation amounting in the different cases to between 2 
and 3.5 millimeters. At 8.30 in the evening the shoots were 
curved upward and apparently had completely recovered from 
wilting. Between this hour and 7 o’clock in the morning, when 
still turned upward and apparently very turgid, they showed 
an elongation varying in the different cases between 4 and 5 
millimeters. By 8 o’clock, after having been exposed for a 
short time to the sun, one of them had decreased in length 0.5 
millimeter and another had elongated 0.5 millimeter, while the 
other two had shown no change. The shoots at this time were 
curved downward slightly. By 9 o’clock all of them were vis- 
ibly wilted, and all had shortened either 1 or 1.5 millimeters. 
At 10 o’clock they were very much wilted, and all except one 
