64 THE ENTOMOLOGIST. 
while others, becoming more elongate, quit the earth as 
pupa-nymphs, furnished with rudimentary alary appendages, 
emerging in the winged state from July to September. But 
the development of the race does not terminate here, on 
attaining the winged condition. In an interesting memoir, 
‘Sur le Phylloxera aile et sa progéniture,’ M. Balbiani has 
shown that these winged females (to which no males are 
ascribed) deposit their eggs, two to five in number, amid 
the down of the young vine-leaves, when in captivity; from 
which eggs an apterous sexual race is derived, as previously 
described by him (in 1873) in the case of the Phylloxera of 
the oak (P. Quercus of Fonscolombe), these eggs being of two 
different dimensions, the larger producing females, and the 
smaller males, both sexes destitute of organs of nutrition, 
the promuscis being reduced to a short flattened tubercle, 
and the female having the third joint of the antenne 
pedunculated. The same diligent observer has more recently 
ascertained that the subterranean brood of the Phylloxera of 
the vine is also continued from year to year by a similar 
sexual race, which appears later than that derived from the 
winged type (about the middle of October), but perfectly 
identical therewith, the females of both producing only a 
single egg (l’aeufWhiver of Balbiani); whereby, in the one 
case, the continuity of the race is maintained for several 
years upon the same root until this is entirely exhausted ; 
while, in the other, by the intervention of the winged type, 
new colonies are dispersed far and wide. M. Balbiani also 
states that certain abnormal forms, occasionally found mingled 
with the winged type, noticed by him in several other species 
and formerly considered as males, are rather to be regarded 
as females with atrophied characters, somewhat analogous to 
the neuters of social Hymenoptera. Some strange theories, 
however, have been propounded by M. Lichtenstein, as to 
certain phases in the genetic cycle of the race, whereby it is 
alleged that the winged Phylloxera of the vines resort to the 
Kermes oak (Quercus coccifera) to deposit—not eggs, but 
—pupe, from which such sexual race is developed as 
aforesaid; this winged type being characterized as ‘‘ Andro- 
phores” and “Gynéphores,” according to the sex of the 
pupe deposited by these so-called “flying cocoons.” 
M. Balbiani, however (on examining other specimens taken 
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