This is only an insignificant trace of some albuminous secretion accompanying the egg or facilitating the work of the double saw of the oviduct.
Immediately below the aperture of the perforation is the egg chamber: a short, tunnel-shaped cavity which occupies almost the whole distance between one opening and that lying below it.

Sometimes the separating partition is lacking, and the various chambers run into one another, so that the eggs, although introduced by the various apertures, are arranged in an uninterrupted row.

This arrangement, however, is not the most usual.
The contents of the chambers vary greatly.

I find in each from six to fifteen eggs.

The average is ten.