32 
BULLETIN 911, IT. S. DEPARTMENT OF AGRICULTURE. 
Cocooning began as early as August 15 and continued until 
October 31. 
PERCENTAGE OF COCOONING PREVIOUS TO AND DURING GRAPE 
HARVEST. 
Table XXXVI. — Percentage of cocooning previous to and during grape harvest, San- 
dusky, Ohio, 1918. 
Time. 
Date. 
Number 
of 
cocoons. 
Percent- 
age of 
total. 
To Sept. 20........ 
Sept.2Q-Oct.10..'. 
To Oct. 10 
343 
342 
685 
670 
821 
21 
40.73 
40.62 
81.35 
To Oct. 8 . . 
79.57 
To Oct. 26 
97.50 
To Nov. 1. 
2.50 
The data in Table XXXV are summarized in Table XXXVI and 
emphasize similar records for the seasons of 1916 and 1917. From 
these records of three seasons involving a large quantity of larvae 
regularly collected it must be concluded that a very large part of the 
second-brood larvae leave the fruit previous to and during the early 
part of grape harvest. 
MISCELLANEOUS RECORDS. 
In the course of the life-history studies some observations were 
made that have a bearing on the habits of the insect and the develop- 
ment of the different stages. 
ADULT. 
The pupae formed in the fall of 1916, from which moths emerged in 
the spring of 1917, were kept through the spring emergence period of 
1918 to determine if any pupae lived over and emerged the second 
spring. No moths emerged from this material the second year. 
In an effort to approach natural conditions for moths in confine- 
ment dilute strained honey was supplied in the rearing jars. The 
usual observation was that the moths were not attracted to the food, 
but would feed if they came in contact with it. In one case when no 
new food had been supplied for six days, upon placing water on the 
sand in the bottom of the cage two moths immediately went \\ inches 
to the water and appeared to drink of it. 
The adults seldom are seen in the vineyards during the day, and 
throughout these investigations, though the writer was in heavily 
infested vineyards almost daily, moths were rarely observed. In 
one case a moth was seen resting on a young cluster of grape buds, 
another was observed on the upper side of a grape leaf, and a third 
adult was seen in flight about the lower part of a grapevine. It 
alighted on a cane, ran into the angle of a small stub on the cane, 
and rested there, its head in the angle. 
