We often see girls who are not yet thirteen, who still wear short clothes and go to school, that menstruate regularly, but with this precocious menstruation there is also a corresponding development of the body which gives them a womanly appearance. Such girls should not be permitted to expose themselves to the inclemency of the weather, because they are much more liable to take cold, which may result in inflammations, than girls in whom the menses have not appeared. Girls of a scrofulous taint or other hereditary habits of constitution, often begin to menstruate prematurely; outdoor exercise and cod liver oil with cold sponging on retiring at night are the proper resources for building them up. AMENORRHŒA. This term is employed for the purpose of designating an absence of the menstrual flow in persons who are old enough to menstruate, and in whom there is no physiological reason for its suppression, such as being too young, after the change of life, or during pregnancy and while nursing the child on the breasts. We find this disorder of the natural function of menstruation more among the women of the rich and affluent whose lives are spent in indolence and luxury; this is to be ascribed to lack of sufficient exercise to stimulate the nervous and sanguineous systems to the performance of their healthy functions. The amenorrhœa, or a retarded menstruation in young girls, is oftener the result of a general debility than of a disease of either the womb or ovaries. We have here again about the same causes playing their pernicious role as in precocious menstruation in weakly children; that is, that the same causes produce directly opposite results. The scrofulous and hereditary taints always interfere with the proper and healthy development of the system; in amenorrhœa they appear to be a hindrance to the formation and growth of the red blood corpuscles. In some girls the suppression of the courses appears to be a wise conservative provision of nature, because the girls are already so weak and bloodless that even the loss of a very small amount would only increase the anæmia, so that in these cases it is not so much a question of “bringing on the courses” as of building up the constitution, and enriching the blood in order to bring about the desired result. Chlorosis, or the green sickness, is not simply an anæmia or a bloodlessness, but a physiological incapacity of the system to prepare the required blood cells for the sanguineous fluid, and this is, indeed, the most frequent cause of the disorder under consideration. Chlorosis is a disease that is peculiar to the female sex, beginning as a rule at the age of approaching puberty, between the fourteenth and twentieth year, so that there appears to be a physiological relation between the blood genesis on the one hand, and the development of womanhood on the other.