December, ’23] 
deong: habrobracon parasite of plodia 
551 
without the best equipment for such type of work. The temperature 
range was from 24° to 30° C. (75° to 86° F.) to simulate natural conditions 
in the ordinary warehouse of interior California during the summer. 
Life History Data of Habrobracon juglandis 
No. 
Number of 
Specimens 
Length of 
egg stage 
Length of 
larval stage 
Length of 
pupal stage 
Period from 
egg to adult 
1 
7 
Days 
2 
Days 
6 
Days 
6 to 8 
Days 
14 to 16 
2 
2 
— 
— 
7 to 8 
— 
3 
7 
2 
5 to 7 
6 to 7 
15 to 16 
4 
5 
3 to 4 
4 to 5 
10 to 11 
18 to 20 
5 
5 
3 
4 to 5 
— 
— 
6 
8 
2 
5 
—• 
— 
7 
6 
2 to 3 
4 
10 
16 to 17 
8 
4 
3 
5 
—■ 
— 
9 
1 
3 
4 
5 
12 
10 
6 
2 to 3 
7 
— 
—• 
11 
3 
2 
5 to 8 
-—■ 
— 
Average 
2.6 
5.2 
7.4 
16 
The average development period of Plodia interpunctella under 
California conditions is given by Parker (former citation) at fifty-three 
days. Comparing this with the average period of sixteen days from 
egg to adult of the parasite, it will be seen that there is a possibility of 
three and a partial fourth generation to one of the host. 
Oviposition Habits.. The caterpillars frequently recognize the para¬ 
site as a possible enemy and may attempt to escape from it. After 
being stung, however, paralysis occurs in twenty to twenty-five minutes 
and then from one to three pearly white eggs are attached to the cater¬ 
pillar. Three parasites were occasionally reared from one mature 
caterpillar, but in one instance when five eggs were deposited on a single 
host four larvae matured but only one adult emerged. Many cater¬ 
pillars that were confined with parasites were stung and paralyzed even 
though no eggs were deposited upon them. In one instance eleven 
Plodia larvae and one female parasite were confined in a vial and within 
two hours all the caterpillars had been paralyzed. Some of these were 
kept for three weeks and at the end of this time they had shriveled up 
and turned black, but the exact time of death could not be determined. 
Oviposition began in one or two days after the adults emerged and 
continued over a period of from seven to nine days. The total number of 
eggs recorded from a single parasite ranged from fifteen to twenty-four. 
