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as the affected locality is near the headquarters of an active fruit- 
growers' association, remedial work is in proper train. Dividing the 
expense between the station and fruit-growers, California washes have 
been applied with care and thoroughness, and at last reports a deter- 
mination existed to repeat the application as often as might be neces- 
sary before spring. 
LIFE -HISTORY OF THE INSECT. 
Although this insect has been known in California for about twenty 
years, its life-history has not been carefully worked out by California 
writers. Professor Comstock described simply the male and female 
scales, and the body of the adult female. The male was unknown to 
him. In his work on the Injurious Insects of the Orchard, Vineyard, 
etc., published at Sacramento in 1883, Mr. Matthew Cooke briefly 
described the male insect and published a crude figure of it. He fur- 
ther stated that the species produces three broods in California, the 
first ki about the time the cherries begin to color, the second in July, 
and the third in October. " The statement is made by Comstock that 
the eggs are white, and Cooke further says that "each female produces 
from 35 to .30 eggs." 
Upon the appearance of the insect in the East, potted pear trees 
were secured for the In sectary of this Division, and colonies of the 
scale were established on them. Their life-history has been followed 
with more or less care throughout the season, and the following brief 
statement of the life-cycle of the insect is based upon daily observa- 
tions made during the summer by Mr. Pergande. 
It had already been ascertained during the late summer and fall of 
1893 that the insect is viviparous, that is, gives birth to living young, 
and that it does not lay eggs. We were unable to reconcile this con- 
dition of affairs with the statements just quoted from Comstock and 
Cooke, but it occurred to us that, as with certain of the plant-lice, 
there might be winter eggs, with viviparous females in summer. When 
winter came on, however, it was found that the insect hibernated in 
the nearly full-grown female condition, and that these females, about 
the middle of May, began to give birth to living young as their ances- 
tors did the previous fall. In no instance, therefore, have we observed 
the egg (unless the young still in the body of the female and enveloped 
in the embryonic membrane may be so called). Over wintered females 
continued to give birth to liviug young day after day for six weeks. 
This condition of affairs produces, early in the season, a confusion of 
generations, which makes observations upon the life-history of the 
insect extremely difficult, and only to be accomplished by isolation of 
individuals. It also seriously complicates the matter of remedies, 
since, as numbers of the larvae are hatching every day. and as they 
begin to form their almost impervious scales in two or three days, a 
spraying operation at any given time will destroy only those larva' 
