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which happen to be at that time less than three days old, while on the 
day after the spraying new larvae will be born to take the place of 
those just killed. 
Observations upon isolated individuals show that the newly -hatched 
larvae, after crawling about for a few hours, settle down and commence 
at once to form a scale. The secretion is white and fibrous. In two 
days the insect becomes invisible, being covered by a pale, grayish- 
yellow shield, with a projecting nipple at the center. This nipple is at 
first white in color. Twelve days after hatching the first skin is cast. 
The males at this time are rather larger than the females, and have 
large purple eyes, while the females have lost their eyes entirely. The 
legs and antennae have disappeared in both cases. Six days later the 
males begin to change to pupa, while the females have not yet cast the 
second skin. At this time the females are so tightly cemented to the 
scale that they can not be removed without crushing. In two or three 
days more, or twenty to twenty-one days after hatching, the females 
cast their second skin, which splits around the margin of the body. 
At 24 days the males begin to issue, emerging from their scales, as a 
general thing, at night. At 30 days the females are about full grown, 
and embryonic young can be seen within their bodies; and at from 33 
to 40 days the larvae begin to make their appearance. 
These observations were made upon young which were born of over- 
wintered mothers late in June, but it must be remembered that similar 
larvae had been hatching since the middle of May. The period of 38 
to 40 days may be accepted as the length of time occupied by a single 
generation; but, while this particular generation came out in the 
insectary about the first of August, the adults of the second generation 
from the earliest-born individuals would have made their appearance 
toward the end of June. Full-grown females which began to give 
birth to the second generation of young on August 1 were kept in 
view. Three weeks later they were seen still to contain numerous 
embryos. Young larvae were running about, while others of the same 
generation were in all stages of development. The male scales were 
fully formed, and some contaiued mature pupae. The small trees upon 
which these insects were colonized the third week in June were almost 
completely covered with the scale. The larvae evidently made no effort 
to crawl away from the tree, and none, in fact, reached the rim of the 
flower-pot. The greatest distance away from the tree at which larvae 
were noticed was about two inches. Up to this time the insects had 
confined themselves almost entirely to the branches, and the leaves 
were still quite free. The first males of the second generation were 
noticed on August 27. By September 7, or five weeks and a half after 
the adult females of the first brood began to give birth to young, some 
of them were still living and giving birth to occasional young. The 
majority of them, however, were dead, or nearly exhausted, while their 
first larvae were almost ready to reproduce. Five days later a few of 
