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partly grown larvae show the stages of transition from six to eight 
segments. In young larvae the division between segments two and 
three is frequently obscure ; in the large females the suture between 
segments two and three, or three and four, is obscure. 
Mr. Pettit, who studied summer females, intimated that the win- 
ter specimens from which the original description was made were 
male pupae. A study of the types, however, has shown me that they 
are females, some of them being full grown, tho they resemble the 
male pupae to the extent of having only seven antennal segments. 
The necessity for using the name Pseudococcus for the genus 
formerly called Dactxlopius has been explained bv Cockerell (Ann. 
Mag. Nat. Hist., Ser." 7, Vol. IX., 1902, pp. 453, 454). 
Life History. — The first account of this coccid was given by Dr. 
Forbes, who found the species on the roots of white clover May 3, 
at Normal, 111. He found that the coccids "were protected by a 
small yellow ant, Lasius ilavus, in whose nests they occurred, and 
were carried away by them like plant-lice when the nest was exposed." 
The general course of the life history has been made known by 
G. C. Davis from his studies in Michigan. He found the coccids 
abundant in clover fields April 27, and attended by Lasius niger. 
When the nests of the ant were opened, the ants carried away these 
coccids to another location. These were winter females. Davis put 
some of them on potted clover and obtained young, the first appear- 
ing May 15; these "gathered under the mother bug or collected in 
the flocculent mass back of her that she had secreted while producing 
them. They were of a light, translucent flesh-color, and much flatter 
than the mother." 
The oviparous female makes a nest of waxy threads and places 
therein 75 to 300 eggs. "At first she is large and plump, but, as 
the pile of eggs increases, she decreases in size until at last there is 
nothing left of her but a little dry wrinkled piece of lifeless skin, and 
a mass of eggs back of her that will measure two or three times as 
much as she did a short time before. The time required for the eggs 
to hatch, and the young mealy bugs to reach maturity, is only about 
six or seven weeks." 
The mealy bugs, tho numerous in the latter part of summer, dis- 
appear in the fall, according to Davis, who failed to find them in any 
stage October 15 where only a few weeks before they had been plen- 
tiful. He suggested that they had changed to the winter form and 
had been carried off by the ants. 
Davis found also that the male, when about half or a third the 
size of the full-grown female, crawls up to some part of the plant 
above ground, spins a fluffy cocoon, and comes out, in less than a 
week, as a winged adult. 
In Urbana, the winter females of various sizes occur on the roots 
of clover, attended by ants, in early spring. Our earliest dates are 
March 24 and 26, but the females could doubtless be found thniout 
