CONTROLLING SEX IN BUTTERFLIES. 519 
any influence in determining sex in the individual once out of the 
egg, I do believe, with Thomas Meehan, Henry Hartshorne and 
others, that there is a certain relation between organic vigor and 
sex, and that the latter may be determined in the offspring by the 
amount of vigor or vitality — creative or organic force —in the 
parents, and that the female is in some way connected with in- 
creased, and the male with lessened, vitality; for strong argu- 
ments may be adduced in favor of such a belief.* Certain curious 
facts in the natural history of some of our gall-making Cynipide 
lend singular weight to these views. From these facts, ascer- 
tained by Mr. H. F. Bassett of Waterbury, Connecticut, there can 
be little doubt that many of the species produce two distinct 
kinds of galls, alternating with each other, the one vernal, the 
other autumnal. The former produce flies with a due proportion 
of the sexes, and the latter produce nothing but large females.f 
In other words, the directly fecundated and more highly vitalized 
ova produce nothing but large females, while the parthenogenetic 
offspring is smaller and composed of both males and females. 
The curious facts, as now understood, in the economy of the 
common hive-bee, seem at first to militate against the conclusion 
that food has no influence on the sex of larvae, but in reality they 
do not, though they indicate that the sex may be altered or deter- 
mined after partial or imperfect conception has already taken 
place. All eggs not directly impregnated produce drones or males 
(not females, as “A.S.P.” by a singular lapse of thought, has 
stated on p. 177 of the March number of the Naruratisr), while 
AMERICAN NATURALIST, Vi, pp- 692, 747, and Missouri Entomological Reports, 
iy, p. 65 and v, p. 85. 
tTo givea single illustration: A large wool gall—the modification and deformation 
of a bud—is tolerably common on our black oaks. The flies produced from it (Cynips 
Q. operator) are bisexual. Mr. Bassett has witnessed the female depositing in acorns 
of same trees on which the wool galls occur- The product of these eggs ip- 
nite irregular in pea pei t with the ‘apical | end tapering more bed pee 
toa kent boat the basal end rounded. It is greenish when ban Aperen 
ture, and the larva rests in a cream-colored ovoid cell, easily freed fro a wet 
covering. This gall is g ough to pee “ihn acorns pea and 
ve known it since 1809. “In ; August. 1871, while visiting Mr. Te ected a 
number from @ he hope of the flies 
from them. This spring, after a lapse of a twenty months, and just as the oak 
buds were bursting I succeeded in obtaining a number of flies, eyery one of them fe- 
males and Sirenis wit h C.q . operator exce ept in being larger. Si ngulayiy saouri this 
year M the woolly 
eani e T operator, ovipositing in buds; and his description leaves no doubt that the 
