The picture describes the reproduction of butterflies.
Overall, there are various steps in the life of a common butterfly, starting with the eggs being laid in the leaf by the female butterfly and ending with two mature ones mating to produce eggs again.
At the beginning of the process, the eggs is laid by their mother in the plant. Subsequently, because each of these eggs contains one embryo, they gradually develop around two-three weeks before growing into caterpillar. At which point, it takes two months for the caterpillars to develop their skin-shedding.
The process continues with the pupa being created by the caterpillars during two hours. This is followed by the pupal stage when the metamorphosis occurs in two weeks, at which point, the caterpillar change their body shape and grow to two wings to become a adult butterfly. Finally, the cycle begins again when two fully-grown butterflies, which are capable of reproducing.