It is necessary to say a few words to explain this book.

The original title of the book was "Musings on Woman and Labour." It is, what its name implies, a collection of musings on some of the points connected with woman's work.
In my early youth I began a book on Woman.

I continued the work till ten years ago.

It necessarily touched on most matters in which sex has a part, however incompletely.
It began by tracing the differences of sex function to their earliest appearances in life on the globe; not only as when in the animal world, two amoeboid globules coalesce, and the process of sexual generation almost unconsciously begins; but to its yet more primitive manifestations in plant life.

In the first three chapters I traced, as far as I was able, the evolution of sex in different branches of non-human life.