10 BULLETIN 911, U. S.' DEPAKTMEN/T OF AGRICULTURE. 
PERCENTAGE OF EMERGENCE OF SPRING MOTHS. 
Table XII. — Percentage of emergence of spring moths of the grape-berry moth from 
hibernation under a leaf blanket in insectary yard, Sandusky, Ohio, 1917 . 
Lot No. 
Source of material. 
Number 
of 
cocoons. 
Number 
of moths 
emerged. 
Emer- 
gence. 
1 
Collected as larvse at Venice, Ohio, 1916 
2,082 
1,493 
2,371 
82 
780 
236 
231 
12 
Per cent. 
37.46 
2 
Collected as larvae at Putin Bay, Ohio, 1916 
15.80 
3 
Collected as larvse at Kellevs Island, Ohio, 1916 
9.74 
4 
14 63 
Total 
6,028 
1,259 
20.88 
No explanation is offered for the variations in percentages of 
emergence from material collected at the different places. The ma- 
terial was all collected as larvse in the infested grapes at similar 
times and kept under identical conditions after collection. That hut 
20 per cent of the cocoons formed withstood the winter under a light 
leaf blanket indicates that the natural mortality is considerable. 
TIME OF DAY OF MOTH EMERGENCE. 
Kecords were taken as opportunity offered on the time of day of 
moth emergence. These records were in the period July 8 to July 
17 or about in the middle of the emergence period. They indicated 
in a general way that emergence began in the morning as soon as the 
heat of the day was felt and that practically all emergence took place 
between 6.30 a. m. and noon. 
OVIPOSITION BY THE SPRING BROOD OF MOTHS. 
A few records of oviposition were secured and are shown in Table 
XIII. These meager records serve only as an indication of the actual 
conditions prevailing. 
Table XIII. — Oviposition of spring moths of the grape-berry moth in rearing cages, 
Sandusky, Ohio, 1917. 
Number of 
moths. 
Date of— 
Days— 
Observation No. 
e 
? 
Emer- 
gence of 
moths. 
First ovi- 
position. 
Last ovi- 
position. 
Before 
ovipo- 
sition. 
Of ovi- 
posi- 
tion. 
From 
emer- 
genceto 
last 
ovipo- 
sition. 
1 
2 
4 
10 
10 
12 
11 
June 18 
June 27 
July 18 
July 20 
July 23 
June 21 
July 2 
July 21 
July 22 
July 24 
June 24 
July 2 
July 23 
July 26 
July 28 
3 
5 
3 
2 
1 
4 
1 
3 
5 
5 
6 
2 
3 
4 
5 
10 
4 
4 
2 
5 
5 
6 
5 
2.8 
3.6 
5.4 
