We then see broken layings, beginning with females and ending with males.
The egg, as it issues from the ovary, has not yet a fixed sex.

The final impress that produces the sex is given at the moment of laying, or a little before.
So as to be able to give each larva the amount of space and food that suits it according as it is male or female, the mother can choose the sex of the egg which she is about to lay.

To meet the conditions of the building, which is often the work of another or else a natural retreat that admits of little or no alteration, she lays either a male egg or a female egg AS SHE PLEASES.

The distribution of the sexes depends upon herself.

Should circumstances require it, the order of the laying can be reversed and begin with males; lastly, the entire laying can contain only one sex.
The same privilege is possessed by the predatory Hymenoptera, the Wasps, at least by those in whom the two sexes are of a different size and consequently require an amount of nourishment that is larger in the one case than in the other.