July 8, 1918 
Toxoptera graminum in the South 
103 
Table I. —First and last born generations, date of birth, reproductive period, in days , 
daily average and total number of young, total length of life , and maximum and minimum 
temperature during which each generation of Toxoptera graminum lived . Columbia, 
S. C., IQ13-1915-— Continued 
series a— continued 
Generations. 
Repro- 
ductive 
period. 
Young. 
Length 
of life. 
Temperature. 
First¬ 
born. 
Last- 
bora. 
1 Dates. 
Daily 
average. 
Total. 
Maxi¬ 
mum. 
Mini¬ 
mum. 
T 9 r 3 - * 9 * 3 -' 
Days. 
Days. 
0 F. 
0 F. 
21 
Aug. 20 to Sept. 25.. 
21 
3 - °4 
64 
36 
93 
48 
6 
21 to 15.. 
18 
2. 88 
52 
25 
93 
56 
22 
2 7 to II.. 
IO 
3, 20 
32 
15 
93 
61 
23 
Sept. 1 to 29.. 
20 
2. 50 
50 
28 
92 
48 
24 
8 to Oct. 8.. 
21 
3 - i 4 
66 
30 
9 i 
48 
7 
13 to 16.. 
21 
2. 04 
43 
33 
88 
47 
25 
20 to Nov. 17.. 
32 
2. 00 
64 
58 
86 
26 
26 
29 to Dec. 10.. 
42 
1. 66 
69 
72 
86 
24 
27 
Oct. 7 to Nov. 24.. 
46 
1. 71 
77 
48 
85 
28 
8 
10 to 15.. 
26 
1. 07 
28 
3 6 
85 
26 
28 
16 to Dec. 11.. 
41 
1.68 
69 
56 
78 
24 
! 9 i 4 . 
29 
Oct. 29 to Jan. 30.. 
5 2 
1. 16 
61 
93 
78 
24 
9 
Nov. 14 to 28.. 
62 
1.30 
81 
75 
78 
24 
30 
18 to Feb. 12.. 
60 
1. 36 
82 
86 
78 
24 
31 
Dec. . 3 to 3.. 
53 
1. 01 
54 
62 
74 
21 
1914 . 
32 
Jan. 7 to Feb. 21.. 
17 
•47 
8 
45 
74 
24 
10 
24 to Apr. 13.. 
23 
3 - 30 
76 
79 
78 
21 
33 
Feb. 2 to 20.. 
41 
5 i 
62 
77 
84 
21 
34 
Mar. 7 to 29.. 
23 
2. 26 
52 
53 
92 
29 
35 
28 to May 12 .. 
29 
3-03 
78 
45 
92 
40 
11 
Apr. 3 to 14.. 
27 
2. 74 
74 
4 i 
92 
40 
3 <> 
7 to 2.. 
10 
3 * 50 
35 
25 
92 
40 
37 
19 to 12:. 
8 
3 - 50 
28 
23 
92 
40 
3 « 
28 to 23.. 
16 
2. 18 
35 
25 
93 
52 
39 
May 6 to 30.. 
14 
3 - 85 
54 
24 
93 
52 
12 
9 to June §.. 
22 
3 ' 5 ° 
77 
30 
96 
52 
40 
13 to May 30.. 
4 
5-00 
20 
17 
99 
55 
4 i 
21 to June 21.. 
13 
4 - 38 
56 
3 i 
99 
56 
42 
20 to 20.. 
17 
4. II 
70 
23 
99 
61 
43 
June 2 to 29.. 
14 
3 - 8 S 
54 
27 
103 
60 
13 
s to July 2.. 
17 
2.35 
40 
27 
103 
60 
44 
9 to June 21.. 
12 
I. 50 
18 
12 
98 
60 
45 
14 to 26.. 
2 
i-. 5 ° 
3 
12 
103 
60 
46 
22 to July 25.. 
20 
2. 65 
53 
33 
103 
62 
47 
29 to 20.. 
39 
1-25 
49 
21 
98 
62 
14 
29 to 23.. 
16 
2. 62 
42 
24 
98 
62 
48 
July 6 to 27.. 
13 
2. 38 
3 i 
21 
102 
67 
49 
13 to 28.. 
7 
3 - 58 
25 
15 
102 
61 
5 ° 
19 to Aug. 22.. 
17 
3 - 05 
52 
34 
102 
61 
15 
20 to 19.. 
19 
2- 57 
49 
30 
102 
61 
5 i 
27 to 31.. 
17 
3- 64 
62 
35 
98 
68 
52 
Aug. 3 to 21 . 
13 
4. 00 
S 2 
18 
93 
68 
53 
8 to 31 . 
15 
3.66 
55 
23 
94 
69 
16 
13 to Sept. 16.. 
15 
3 - 53 
' 53 
34 
94 
^3 
54 
14 to 9.. 
12 
4. 66 
56 
26 
94 
39 
55 
20 to 19.. 
23 
1.78 
41 
30 
94 
69 
56 
27 to Oct. 10.. 
20 
2. 60 
52 
44 
94 
39 
57 
Sept. 2 to 17.. 
16 
4 - 56 
74 
45 
94 
39 
17 
3 to 12 .. 
23 
i. 86 
43 
39 
94 
39 
58 
8 to 19.. < 
17 
4. 00 
68 
4 i 
94 
33 
