The fact that natural folliculoids,1 such as estradiol or estrone, and artificial folliculoids, such as stilbestrol, are effectively absorbed through the skin has been demonstrated by numerous investigators.2 It has been found, for instance, that in the mouse inunction of the skin with solutions or suspensions of folliculoid compounds causes typical estrous-like changes in the internal sex organs. Although it has often been claimed that in certain cases folliculoids may act as carcinogens, none of the aforementioned investigators were able to produce cutaneous changes resembling cancer by the local application of the folliculoids to the skin.
That folliculoids may elicit some local action on the skin has been shown by Steinach,3 who found that cutaneous hyperemia may be induced by such compounds in the rat. Argüello4 observed, in the same species, great diminution in the number of hair follicles and hyperplasia of the cornified layer after