FIG. 2. Zygotes from wild X wild (Al to A4) and mutant X wild
(B1 to B4) crosses. JC1 X GF4836-8C (wild X wild) and P24 X
GF4836-8C (mutant X wild) mating mixtures were incubated at 300
for different periods of time, and stained with mithramycin according
to the procedure described in Materials and Methods. Al to A3 and
B1 to B3 were sampled after 5 hr of mating; A4 and B4, after 15 hr.
X1120.