The position a posteriori (more pecudum) is not so favorable for the frictions of the clitoris. The female orgasm will hence, at best, be retarded. The prone position is, therefore, not the hygienic ideal, at least so far as the female is concerned. The popular belief that this position is more exciting for male and female is based upon the assumption that the intensity of the libido is proportional to the depth insertionis in vaginam fascini. This belief is erroneous. The radix of the penis, as well as the fornices of the vagina, are, as a rule, the points of the least value for inducing orgasm, and these are the very points most affected by the frictions in the prone position. The portio vaginalis and the os externum which are sexually very excitable are, in the prone position, not easier reached by a normal fascinum than in the supine position. In normal cases,[CO] therefore, the prone position of the female is anti-hygienic. In women with orgasmus retardus of moderate degree, positura viri infra may be of some benefit. This position damps somewhat the male ardor, et impeditæ sunt motiones, dum mulier moveat cito aut lente so as to produce the best effects upon her own orgasm.[CP] _Frequentatio concubitus._—Congressus frequentatio varies with different individuals, but with the majority, under thirty years of age, three times a week should be considered sufficiently frequent, between thirty and forty twice a week, and less frequently as age advances.[CQ] When concarnatio is followed by a sense of relief and comfort it is beneficial, and to be thus guided is the most rational practice. The criterion of marital hygiene, as far as frequency is concerned, is hence the state of the feelings of the couple. The day post initum both mates must feel refreshed in body and spirit, otherwise the act was unhygienic. If one of the mates has greater sexual desires than the other is able[CR] or willing to gratify, he or she has to suppress the erotic excitement by the exertion of will-power or by cold sponging, cold baths and when necessary even by bromides. For while chastity does very little harm to the individual, excesses in venere destroy in time both body and mind.[CS]