The same reason is responsible for the universal tendency among lovers to approach and touch one another’s lips. For, affection fed by sight, sound, taste and odor, reaches its climax in touch. The combined power of contact with softness and warmth amounts to a considerable pitch of material pleasure, and a predisposed affection, as among lovers, renders the contact thrilling. Love pleasure, therefore, begins and ends in sensual contact. The intensity of the sensual pleasure will be proportional with the area of contact and with the dignity of the organs touched. Nudity with the greater area of direct contact will increase the pleasure. The values of the organs producing sexual libido are successively: in the male, glans et corpus penis, scrotum, labia oris, lingua, palma manus, and the gluteal region; in the female, clitoris, vulva, labia majora, nymphae, vestibule, vagina, vaginal portion of cervix, mamillae, labiae oris, lingua, palma manus and the gluteal region.[O] The more points of the highly sensible organs are touched, the larger the extent of the skin-surface that enters into the realm of touch, the more the frictions are conducive to excitation, the better the function of the sphincter cunni,[P] the greater will be the intensity of the sensual libido in both mates. If more special senses are excited, such as sight by beauty, the smell by sweet odors, the touch by soft, smooth skin, if imagination coöperates, and if inhibitory effects are absent, then the intensity is much greater. _Inhibition of libido._—The inhibitory effects upon the libido have various causes, and are mostly brought on by the different senses. The most inhibiting effects emanate from the sense of smell. The sense of smell plays an important rôle in provoking or inhibiting sexual desire. For that reason women are possessed of certain odors to attract their mates.[Q] The vaginal mucus, or rather contents, have a stale, characteristic odor. This odor belongs to the class of the capryl-odors, which may be designated as the specifically erotic odors. The natural vaginal odor becomes stronger during the menstrual period. Some women transpire at the time of menstruation the disagreeable odor of trimethyl-amin. In some country-districts in Europe, it is reported, the young peasants, when going to a dance, place their handkerchiefs into their arm-pits to imbibe the peculiar odor of the man, and, unaware to the girls, hand over the same to the women they are in love with to smell. The peculiar odor is supposed to excite the girls to love.