To Calmann appear to be due the first carefully made observations showing the minor sensibility of the genital tract in women. (Adolf Calmann, "Sensibilitütsprufungen am weiblicken Genitale nach forensichen Gesichtspunkten," _Archiv für Gynäkologie_, 1898, p. 454.) He investigated the vagina, urethra, and anus in eighteen women and found a great lack of sensibility, least marked in anus, and most marked in vagina. [This distribution of the insensitiveness alone indicates that it is due, as I have suggested, to natural selection.] Sometimes a finger in the vagina could not be felt at all. One woman, when a catheter was introduced into the anus, said it might be the vagina or urethra, but was certainly not the anus. (Calmann remarks that he was careful to put his questions in an intelligible form.) The women were only conscious of the urine being drawn off when they heard the familiar sound of the stream or when the bladder was very full; if the sound of the stream was deadened by a towel they were quite unconscious that the bladder had been emptied. [In confirmation of this statement I have noticed that in a lady whose distended bladder it was necessary to empty by the catheter shortly before the birth of her first child--but who had, indeed, been partly under the influence of chloroform--there was no consciousness of the artificial relief; she merely remarked that she thought she could now relieve herself.] There was some sense of temperature, but sense of locality, tactile sense, and judgment of size were often widely erroneous. It is significant that virgins were just as insensitive as married women or those who had had children. Calmann's experiments appear to be confirmed by the experiments of Marco Treves, of Turin, on the thermoesthesiometry of mucous membranes, as reported to the Turin International Congress of Physiology (and briefly noted in _Nature_, November 21, 1901). Treves found that the sensitivity of mucous membranes is always less than that of the skin. The mucosa of the urethra and of the cervix uteri was quite incapable of heat and cold sensations, and even the cautery excited only slight, and that painful, sensation.