As it now stands, I trust this treatise answers the purposes for which it was intended. I have taken care to make it so complete, and scientific, that a medical student may take it for his text book; and at the same time I have endeavoured to so simplify it that any female, of ordinary capacity, can fully understand both its explanations and practical directions. All purely technical words have been avoided, or, when absolutely necessary, they have been carefully explained. Every topic connected with the main subjects has been discussed, and the latest information given on every point, and from every source. Such a work as this has long been needed. Females have been kept in shameful ignorance, of everything connected with their own systems, and of the wonderful phenomena in which they play so important a part. That ignorance has led to untold evils, which can never be corrected till they become more enlightened respecting themselves. Fortunately many of them begin to see this, and they request, in behalf of themselves and their sisters, that such knowledge be no longer withheld. I have been now, for a long time, engaged in this pleasing task of female instruction, both by my Lectures and books, and in my daily communion with them as patients; I am therefore aware both of their great lack of proper information, and of their strong desire for it, and I flatter myself I also know, from experience and careful observation, the best mode of imparting it to them. In fact, I have made it a matter of careful study, not only to render my subject _plain_, but also _pleasing_ and _unobjectionable_; so that the most unreflecting shall feel an interest in it, and the most sensitive be able to study it without pain or repugnance.