Fortunately, modern science has thrown some light on this subject and disproved the theory that its absence was necessarily due to a woman's having had sexual relations. There are cases on record of women who have lived four and five years in prostitution who were found with perfectly preserved hymen. It is important to know that it differs in size and shape in women. Also, that in some women it has been entirely absent since birth. Many little girls and babies have no hymen. It can be destroyed by accident or injured by operations, or examinations where the physician did not use the greatest care. In some women it is easily destroyed; in others it is more difficult. It is not at all uncommon for a physician to find the hymen unruptured when he comes to deliver the first born child. All of which goes to prove that neither its presence nor its absence is necessarily the sign of virginity. Now that we have some idea of the situation of the reproductive organs and their relations to one another we shall be ready to consider in greater detail the ovule or egg in the ovary. PUBERTY—PART II. Beginning with puberty the eggs from the ovary are expelled as they ripen or mature. This process is called ovulation and occurs about every twenty-eight days. It is closely related to menstruation, but it is not menstruation as you will soon learn. Some writers say the egg is expelled at other times than at the menstrual periods; another writer asserts that one passes every six hours, alternating male and female. There are many views and ideas on the subject of ovulation, but I will tell you of the most generally accepted theory, that the egg is expelled from the ovary every twenty-eight days. When the egg ripens, the ovary discharges it and sends it on to find its way through the tubes to the uterus. Here we find the blood supply of the uterus greatly increased in preparation for the egg. We find the inner lining of the uterus becomes very soft and smooth so that the egg can very easily find a place in which to lodge itself after it has been fertilized. We also find that the cells swell and multiply, all in preparation to welcome and nourish the incoming egg or ovum. If the egg is fertilized by the male, it then remains in the uterus to develop. If not, it is thrown out, together with all the preparation made to receive it. The cells burst and discharge their contents; the mucus, blood, cells and all come away in what is called the menstrual flow.