THE GRAPE PHYLLOXERA IN CALIFORNIA. 
93 
In 1915, in all, there were reared to maturity 52 sexuals, of which 
9 were males, 2 of these having hatched from eggs of intermediate 
dimensions. These 2 males were noticeably larger than the other 7. 
The majority of the sexuals were reared in darkness under cellar 
conditions, the temperatures never averaging over 70.5° F. and in 
one instance falling to 61.5° F. A noticeable phenomenon was the 
death of a great number of sexes during the fourth instar, which 
appeared to be due to their inability to cast the final skin as a result 
of a deficiency of moisture. Tables XXXII and XXXIII show 
the development of the sexes in 1915. 
Table XXXII. — Development of sexed forms of the grape phylloxera, Walnut 
Greek, Calif., 1915. 
Individual No. 
Date of 
egg de- 
position. 
Date of 
maturing 
of sexual 
Develop- 
mental 
period. 
Sex. 
Average 
tempera- 
ture. 
Environment. 
July 17 
...do..... 
...do 
July 28 
..do 
.do. 
...do..... 
...do 
July 18 
July 22 
...do 
...do 
July 30 
July 31 
...do 
July 30 
...do 
July 28 
Aug. 2 
Aug. 3 
...do 
Aug. 8 
Aug. 10 
...do 
Aug. 1 
...do.... 
...do.... 
...do.... 
Aug. 12 
...do 
...do.... 
...do.... 
...do...., 
..do...., 
Aug. 3 
...do.... 
.do. 
-do. 
-do. 
Aug. 13 
Aug. 14 
Aug. 12 
Aug. 13 
...do.... 
...do.... 
Aug. 4 
Aug. 5 
...do 
...do.... 
...do.... 
..do.... 
..do..... 
..do.... 
Aug. 6 
..do.... 
..do..... 
..do..... 
Aug. 25 
..do.... 
Sept. 1 
Sept. 22 
Sept. 24 
..do..... 
..do..... 
Sept. 26 
..do..... 
Oct. 6 
..do..... 
..do 
Oct. 7 
..do 
Oct. 13 
..do 
..do..... 
Aug. 14 
Aug. 15 
Aug. 16 
.-do 
..do..... 
.-do..... 
..do..... 
..do 
..do 
Aug. 17 
Aug. 18 
..do 
Aug. 19 
Sept. 8 
Sept. 9 
Sept. 15 
Oct. 4 
Oct. 9 
..do 
Oct. 10 
Oct. 12 
Oct. 13 
Oct. 21 
..do 
Oct. 22 
Oct. 24 
Oct. 25 
Nov. 1 
..do 
Nov. 3 
Days. 
11 
11 
11 
13 
13 
10 
11 
12 
12 
9 
10 
10 
11 
11 
11 
11 
12 
13 
9 
10 
10 
10 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
12 
12 
13 
14 
15 
14 
12 
15 
15 
16 
16 
17 
15 
15 
16 
17 
18 
19 
'F. 
70.3 
70.3 
70.3 
70 
70 
69.7 
69.7 
68.8 
68.8 
68.8 
68.8 
68.5 
68.5 
68.5 
68.6 
68.7 
68.7 
66.9 
64.9 
64.9 
64.9 
64.8 
64.3 
64.3 
62 
62 
61.5 
61.5 
61.7 
•Cellar. 
Room of laboratory. 
•Cellar. 
Room of laboratory. 
Cellar. 
Room of laboratory. 
Cellar. 
Room of laboratory. 
Cellar. 
