“…It is not surprising then, that the vaginal epithelium, cultured in the absence of oestrogens, but in a medium stimulating cell division, should respond as though to oestrogens. Mueller [1953Mueller [ , 1954Mueller [ , 1957 and Mueller, Herranen & Jervell [1958] have described the changes occurring in the protein-nucleoprotein metabohsm and morphology of the uterus of the rat 6 hr after systemic administration of oestrogens. These changes could be duphcated by 18 hr incubation of the uterine segments in Eagle's tissueculture medium [Eagle, 1955] in the absence of oestrogens.…”