III.

The Secondary Sexual Skin Centres--Orificial Contacts--Cunnilingus and
Fellatio--The Kiss--The Nipples--The Sympathy of the Breasts with the
Primary Sexual Centres--This Connection Operative both through the Nerves
and through the Blood--The Influence of Lactation on the Sexual
Centres--Suckling and Sexual Emotion--The Significance of the Association
between Suckling and Sexual Emotion--This Association as a Cause of Sexual
Perversity.


We have seen that the skin generally has a high degree of sensibility,
which frequently tends to be in more or less definite association with the
sexual centres. We have seen also that the central and specific sexual
sensation, the sexual embrace itself, is, in large measure, a specialized
kind of skin reflex. Between the generalized skin sensations and the great
primary sexual centre of sensation there are certain secondary sexual
centres which, on account of their importance, may here be briefly
considered.

These secondary centres have in common the fact that they always involve
the entrances and the exits of the body--the regions, that is, where skin
merges into mucous membrane, and where, in the course of evolution,
tactile sensibility has become highly refined. It may, indeed, be said
generally of these frontier regions of the body that their contact with
the same or a similar frontier region in another person of opposite sex,