Mar . 24,1923 
Temperature and Evaporation on Aphis pomi 
977 
Table II .—Daily temperature, evaporation, and precipitation at Corvallis, Oreg., 1920 — 
Continued. 
Date. 
July 30 
3 1 
Aug. 1 
3 - 
4 .. 
5 -- 
6 .. 
7 -- 
8 .. 
9 .. 
10 .. 
11.. 
12 .. 
i 3 - 
14 .. 
IS • 
16 .. 
i 7 -• 
18 .. 
19 .. 
20 .. 
21 .. 
22 .. 
23 ■ 
24 . 
25 * ■ 
26 .. 
. 27 . 
28 . 
29 . 
30 - 
^ 3I * 
Sept. 1. 
2 . 
3 - 
4 - 
5 - 
6 . 
7 - 
8 . 
9 - 
10 . 
11 . 
12 . 
13 - 
14 . 
* 5 - 
Temperature. 
Minimum. 
Mean. 
Maximum. 
°F. 
°F 
°F 
44 
63.8 
83 
40 
6 l. 9 
80 . 
46 
64.9 
87 
45 
63.8 
84 
46 
66.6 
82 
54 
69.4 
89 
53 
66.4 
84 
47 
65.8 
88 
59 
71 . 6 
88 . 
5 6 
65.6 
82 
45 
63-7 
82 
48 
67 . 2 
88 
50 
74-5 
92 
53 
76.9 
100 
47 
74-5 
100 
43 
68.4 
97 • 
45 
67 . 2 
93 
40 
6 l .6 
86 
32 
54 -o 
75 
42 
58.4 
76 
41 
67.6 
88 
42 
67 . 6 
96 
46 
67 . 0 
60 . 7 
94 
42 
85 
56 
67.9 
87 
48 
36 
61.3 
51-9 
77 
70 
43 
58.0 
76 
40 
50.7 
64 
5 i 
57-8 
74 
30 
48 . 2 
67 
37 
54-9 
74 
40 
6 S -3 
85 
4 i 
64 . 6 
90 
40 
62.1 
87 
40 
58-9 
82 
50 
60 . 6 
78 
33 
53-3 
7 i 
32 
5 i -4 
70 
41 
55-4 
74 
* 47 
53-3 
62 
48 
5 i -5 
58 
52 
5 6 -4 
60 
49 
56.9 
69 
48 
54-2 
68 
44 
50-5 
58 
37 
50-9 
69 
4 i 
55-7 
75 
tion. 
Cc 
26.3 
63 .O 
28.5 
3^3 
36 . 6 
21 . 6 
27.7 
53-3 
27 . 6 
30-9 
5°-9 
49-5 
40.9 
Precipita¬ 
tion. 
Character of weather. 
72.9 
32 . I 
23-7 
29 . 6 
47-4 
36-4 
S 2.4 
33-3 
22 .6 
32-S 
3-8 
27.9 
23 . o 
46.4 
32.4 
24-3 
20.1 
33-9 
19 . 7 
16.3 
9-7 
S-o 
3-3 
14 . 2 
i -7 
9.6 
IS- 2 
Inches • 
O 
O 
o 
o 
o 
o 
o 
•°5 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
. 01 
o 
. 22 
. 02 
.49 
o 
o 
o 
o 
o 
o 
o 
o 
o 
o 
.08 
• 23 
. 01 
1.18 
•95 
. 26 
Cloudy. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Partly cloudy. 
Cloudy. 
Partly cloudy. 
EVAPORATION STUDIES 
During the summer of 1919 a series of experiments was conducted in 
the hope that the measurement of atmospheric evaporation—combining, 
as it does, effects of both temperature and humidity—might, under nor¬ 
mal outdoor conditions, give a fairly accurate index to the rate of meta¬ 
bolism of Aphis pomi. The study was continued during the summer of 
1920. 
