An insufficiency of the hæmatopoietic organs as regards their functional capacity is believed by _Kahane_ to be in the case of women so far physiological inasmuch as their blood is inferior to that of men in hæmoglobin-richness and corpuscular richness to the extent of about 10 per cent. In this way the predisposition of the female sex to chlorosis may perhaps be explained. A further fact which must be taken into consideration is the difference between the development undergone by the respective sexes at puberty. In the female sex, this development is quickly completed, and has the characteristics of a revolution; but in the male, the development is a more gradual one, and has the characteristics of an evolution. _F. A. Hoffmann_ also regards chlorosis as associated with the development of the uterus and the establishment of menstruation. It is possible that these processes exercise some reflex influence; but we must also remember that the chemical processes involved in the growth and maturation of the ovarian follicles are still insufficiently understood, and that it is quite possible that these too may have powerful and unaccustomed effects on the organism such as may well disturb metabolic processes of a somewhat unstable character. _Grawitz_, who regards chlorosis as a vasomotor neurosis in which disturbances arise in the interchange of fluids between the tissues and the vessels, refers the appearance of chlorosis at puberty to the general disposition to disorder exhibited at this age by the vasomotor system. Other authors consider chlorosis to be an ovarian auto-intoxication, believing that under certain conditions the ovaries give off into the organism certain poisons; or, on the other hand, supposing that a certain antitoxic function, normally possessed by the ovary, fails. _Von Noorden_, for instance, regards chlorosis as a disorder of blood formation referable to a disturbance of the internal secretion of the ovary during the developmental period. _Blondel_, who also regards ovarian auto-intoxication as causal, is of opinion that chlorosis is induced by products of decomposition formed in the organism during the process of growth. As in childhood the thymus gland, so later in life the ovary, renders these products innocuous. When this peculiar functional activity of the ovary is retarded in its appearance, the intoxication effected by the products of decomposition formed during the process of growth gives rise to chlorosis.