Lactation,
  no intercourse among some savages during
Laughter and the sexual sphere
Leistes superciliaris
Love-bite, the
Love-songs rare among savages
Lycanthropy

Malays,
  coitus among
  courtship among
  sexual instinct in
Mantis religiosa
Maoris,
  marriage by capture among
  sexual instinct in
Marquesans,
  courtship among
  sexual instinct in
Marriage by capture
  in relation to suicide
  in relation to insanity and criminality
Marsh-bird,
  courtship of
Masochism among Slav women
  definition of
  its psychological mechanism
Masturbation in women
Menopause, sexual impulse after
Menstruation and sexual impulse
Micturition and sexual impulse
Mixoscopia,
  hysterical
Modesty among savages
  object of
  obsessions of
Molothrus bonariensis
Moluccas,
  courtship in
Monogamy,
  its advantages for men
Mortality connected with the development of the sexual instinct
Moslems,
  coitus among
Moths,
  courtship of
Motion,
  the pleasure of
  arrest of
Muscular movement,
  auto-intoxication by
Music,
  sexual influence of

Necrophilism
Necrosadism
Negresses not jealous
Negro eunuchs
Negroes,
  sexual instinct in
Neurasthenia, sexual
New Caledonia,
  courtship in
New Guinea,
  courtship in
New Hebrides,
  courtship in
New Mexico,
  courtship in
New Zealand,
  marriage by capture in
Nubia,
  eunuchs in

Obsessions,
  sexual
Octopus,
  courtship of
Odour,
  excitation by
Oneida community
Ooephorectomy and sexual impulse
Orgasm lasts longer in women
Ostrich,
  courtship of
Ovariotomy and sexual impulse
Ovary,
  secretions of
Ox,
  sexual impulse in

Pain the essential element in algolagnia
Palang
Papuans,
  courtship among
  sexual instinct in
Parturition sometimes painless
Passivism
Passivity of women only apparent
Penis in lower animals,
  peculiarities of
Periodicity of sexual impulse among savages
  greater in women
Pitangus Bolivianus
Pleasure,
  in what sense pain may be felt as
  its manifestations resemble those of pain
Plover,
  dances of great
Power in sexual sphere,
  love of
Precocity of women,
  sexual
Pregnancy,
  savages often avoid intercourse during
Probenaechte
Procreation among savages,
  sacredness of
Pro-estrum
Prostitutes’ love of souteneur
Prostitution not found under primitive conditions
Puberty in girls,
  sexual manifestations at

Rais, Gilles de
Rana temporaria
Rape and sadism
Rat,
  sexual instinct of white
Reeves and ruffs
Reflex action,
  instinct and