THE SHARP'HEADED GRAIN LEAFHOPPER. 
Table IV. — Length of nymphal stage of the sharp-headed grain leaf hopper, Tempe. 
Ariz., 1914 — Continued. 
SECOND GENERATION, MAY AND JUNE, 1914. 
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May 15 
May 14 
May 18 
May 16 
May 15 
May 14 
May 15 
May 21 
May 22 
May 25 
May 22 
May 21 
May 18 
May 21 
Days. 
6 
8 
7 
5 
6 
4 
6 
6 
May 26 
May 28 
...do 
May 23 
May 26 
May 25 
May 26 
Days. 
5 
6 
3 
2 
5 
7 
5 
May 31 
June 2 
May 29 
May 28 
May 29 
June 1 
May 28 
Days. 
5 
5 
1 
5 
3 
7 
2 
June 7 
June 6 
June 4 
June 1 
June 2 
Days. 
6 
4 
6 
4 
4 
Days. 
Days. 
June 7 
June 8 
6 
6 
22 
22 
' 4.7 
4 
4.8 
6 
22 
THIRD GENERATION, JUNE AND JULY, 1914. 
June 28 
Do.... 
Do.... 
Do.... 
Do.... 
Av 
July 1 
July 2 
July 1 
June 30 
July 1 
erage- 2 
3 
4 
3 
2 
3 
July 6 
July 5 
July 6 
July 7 
July 4 
5 
3 
5 
7 
3 
Julv 11 
July 13 
July 12 
...do 
July 8 
5 
8 
6 
5 
4 
July 14 
July 18 
July 17 
July 15 
July 13 
3 
5 
5 
3 
5 
July 21 
July 23 
July 22 
July 26 
July 19 
7 
5 
5 
5 
6 
23 
25 
24 
22 
21 
3 
4.6 
5.6 
4.2 
5.6 
23 
FOURTH GENERATION, AUGUST, 1914. 
Aug. 1 
Aug. 4 
3 
Aug. 9 
5 
Aug. 12 
3 
Aug. 16 
4 
Aug. 20 
4 
19 
Do.... 
Aug. 5 
4 
Aug. 10 
5 
...do 
2 
Aug. 17 
5 
Aug. 21 
4 
20 
Do.... 
Aug. 3 
2 
Aug. 8 
5 
Aug. 13 
5 
Aug. 18 
5 
...do 
3 
20 
Do.... 
...do 
2 
Aug. 7 
4 
Aug. 11 
4 
Aug. 16 
5 
Aug. 22 
6 
21 
Do.... 
Aug. 4 
3 
Aug. 9 
5 
Aug. 13 
4 
Aug. 19 

...do 
3 
21 
Do.... 
Av 
Aug. 5 
erage 3 
4 
Aug. 8 
3 
Aug. 12 
4 
3.6 
Aug. 18 
6 
...do 
4 
21 
3 
4.5 
5.1 
4 
20.3 
. 
FIFTH GENERATION, SEPTEMBER, 1914. 
Sept. 2 4 
Sept. 9 5 
Sept. 18 6 
Sept. 28 7 
26 
SIXTH GENERATION, OCTOBER AND NOVEMBER, 1914. 
Oct. 6 s 
Oct. 11 9 1 
Oct. 17 9 
Oct. 23 9 
Oct. 30 
Nov. 9 
34 
1 Total of averages of instars, 25.5 days. 
2 Total of averages of instars, 23 days. 
3 Total of averages of instars, 20.2 days. 
4 About 20 nymphs. 
a Nymphs in second and third instars. 
6 Nymphs in fourth instar. 
7 Sixteen adults. 
s About 15 nymphs, 
a About this date. 
From Table IV it will be seen that it took the nymphs of the fourth 
generation the shortest time for development and growth, being an 
average of 20 days from egg to last molt. While the lengths may 
vary from season to season and from year to year, it is evident that 
during the summer months nymphs develop in about half the time 
of those of the first spring generation. 
