We
tabulated whether an aphid was approached, and if approached,
whether stung or host-fed. We dissected all the aphids from a
given observation period to determine whether eggs were laid.
Aphids were dissected in batches of 5 on glass microscope slides,
each batch placed in a small drop of Ringer’s solution and covered
with a separate cover slip. We counted parasitoid eggs from the
dissected aphids at 40–100 magnification. From these data, we
tabulated the number of aphids approached and stung, and the
number of aphids fed upon or accepted for oviposition. After each
observation, we also killed the female parasitoids in ethanol, dissected
their ovaries in Ringer’s solution mixed with neutral red
stain, and counted the number of mature eggs under 40–100
magnification (neutral red does not pass through the chorion of
mature eggs and thus they remain unstained).