318 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 17 
The moths can be kept alive in cages, usually without much difficulty, 
by feeding them dilute sugar water or placing in the cage a bouquet of 
alfalfa blossoms. The average length of life of fifty-four moths was 
13.5 days. The longest period any moth remained alive was 27 days. 
The maximum number of eggs obtained from any moth in these 
rearings was 588. The average of 25 moths kept under as nearly 
optimum conditions as could be provided was 181 eggs. Records of 
fifty to one hundred eggs deposited in one night by a single female 
were common, and above a hundred not rare. The largest number 
obtained from one individual in one night was 185. Nothing unusual 
or different from closely related moths was observed regarding oviposi- 
tion or copulation. 
The moths are largely inactive during the day, flying only when dis¬ 
turbed. They are active on cloudy days and in the evenings when they 
can be observed feeding at the blossoms of alfalfa and various weeds in 
alfalfa fields. 
In the autumn and early spring, the moths are smaller and darker 
colored, a condition pointed out by Walsh and Riley (1869). These 
darker forms have been given the varietal name of parva by Blackmore 
(1920). 
Natural Control 
The eggs are parasitized by Trichogramma minutum Riley. Since 
eggs are so rarely found in the field, no definite data on natural parasit¬ 
ism is available Parasitism can be readily induced in the laboratory 
by exposing eggs one or two days old to the parasites. The eggs turn 
black and one to four adults emerge in about eight days through a hole 
gnawed in the side of the egg. 
Larvae are parasitized by Tachinids. Relatively few adult parasites 
have been obtained, though efforts were made to rear a great many 
from parasitized larvae. Winthemia quadripustulata Wied. was ob¬ 
tained three times. Parasitism was never observed to be an important 
factor. 
The larvae are subject to a bacterial wilt which kills many in salve 
box rearings. A somewhat lesser number succumbed in cage rearings. 
It was frequently observed in the field, but is apparently dependent on 
weather conditions. 
Birds pick up these larvae along with other lepidopterous larvae in 
alfalfa. Among those observed to feed upon such larvae are grackles, 
robins, English and other sparrows. Certain Nabids and Reduviids, 
