[83] Bergh tentatively suggests, as regards the pubic hair, that its appearance may be due to the upright walk in man and the human position during coitus, the hair preventing irritation of the genitals from the sweat pouring down from the body and protecting the skin from direct friction in coitus. (In both these suggestions he was, however, long previously anticipated by Fabricius ab Aquapendente.) The fanciful suggestion of Louis Robinson that the pubic hair has developed in order to enable the human infant to cling securely to his mother is very poorly supported by facts, and has not met with acceptance. It may be mentioned that (as stated by Ploss and Bartels) the women of the Bismarck Archipelago, whose pubic hair is very abundant, use it as a kind of handkerchief on which to clean their hands. [84] Routh and Heywood Smith have noted that the pubic hair tends to lose its curliness and become straight in women who masturbate. (_British Gynæcological Journal_, February, 1887, p. 505.) [85] Schurig, _Muliebria_, p. 75. Plazzon in 1621 said that in Italian it had a popular name, _il besneegio_. [86] Schurig brought together in his _Gynæcologia_ (pp. 2-4) various early opinions concerning the clitoris as the seat of voluptuous feeling. [87] Hyrtl, _Op. cit._, vol. ii, p. 193. [88] Adler, _Die Mangelhafte Geschlechtsempfindung des Weibes_, 1904, pp. 117-119. [89] The voluptuous sensations caused by sexual contacts producing movements of the womb are probably normal and usual. They may even occur under circumstances unconnected with sexual emotion, and Mundé (_International Journal of Surgery_, March, 1893) mentions incidentally that in one case while titillating the cervix with a sound the woman very plainly showed voluptuous manifestations. [90] Henle stated that fine hairs are frequently visible on the nymphæ; Stieda (_Zeitschrift für Morphologie_, 1902, p. 458) remarks that he has never been able to see them with the naked eye. [91] R.L. Dickinson, "Hypertrophies of the Labia Minora and Their Significance," _American Gynæcologist_, September, 1902. It is perhaps noteworthy that Bergh found that in 302 cases in which the nymphæ were of unequal length, in all but 24 the left was longer. [92] It may be remarked that Bergh believes that the nymphæ, and indeed the external genitals generally, are congenitally more strongly developed in libidinous persons, and at the same time in brunettes, while in public prostitutes this is not usually the case, which confirms the belief that exalted sexual sensibility does not usually lead to prostitution. He adds that prostitution, unless carried on for many years, has little effect on the shape of the external genitals.