Feb. X7. i9*3 
Aplastomorpha vandinei Tucker 
555 
LONGEVITY 
The average female parasite in captivity lived for about 82 days. This 
period is considerably longer than the life of the male, which averaged 
47 days. 
One female parasite that was not allowed to deposit eggs but was fed 
on sugar and water lived from August 19 to December 4, 1920, a period 
of 107 days. 
Parasites confined without food and without weevil grubs lived for 
only a few days; males so confined died by the end of the sixth day and 
females by the ninth. 
COMPARISON OF LIFE-HISTORY STATISTICS WITH THOSE OF SITO- 
PHILUS ORYZA 
With an average length of life about half that of the rice weevil, this 
parasite lays fully as many eggs per day and completes its life cycle in a 
little less than half the time taken by the rice weevil. 
A smaller percentage of females is produced by the parasite, however, 
and several eggs of the parasite may be wasted on one host grub, so that 
the rate of multiplication is below that of the rice weevil and a complete 
control is not obtained. 
Table III gives a comparison of the life-history records of the parasite 
and the rice weevil. 
Table III. — Life-history statistics of Aplastomorpha vandinei and Sitophilus oryza 
compared 1 
Insect. 
Average 
length 
of life. 
Average 
length of 
oviposi- 
tion 
period. 
Average 
number 
of eggs 
laid. 
Average 
number 
of eggs 
laid 
daily. 
Males 
emerg¬ 
ing. 
Females 
emerg¬ 
ing. 
Length 
of life 
cycle. 
Days . 
Days. 
Per cent. 
Per cent. 
Days . 
S. oryza. 
Ill 
93-9 
380 
4 
48 
5 2 
35 
A. vandinei. 
72 
61 
259 
4 
60 
40 
14 
1 Summer records. 
