The Natural Philosophy of Love

Love's general psychology.--Love according to natural laws. --Sexual selection.--Man's place in Nature.--Identity of human and animal psychology.--The animal nature of love.

II. The Aim of Life

The importance of the sexual act.--Its ineluctable character. --Animals who live only to reproduce themselves.--The strife for love, and for death.--Females fecundated at the very instant of birth.--The maintenance of life.

III. Scale of Sexes

Asexual reproduction.--Formation of the animal colony. --Limits of asexual reproduction.--Coupling.-- Birth of the sexes.--Hermaphrodism and parthenogenesis. --Chemical fecundation.--Universality of parthenogenesis.

IV. Sexual Dimorphism

1. Invertebrates: formation of the male.--Primitivity of the female.--Minuscule males: the bonellie.--Regression of the male into the male organ: the rirripedes.--Generality of sexual dimorphism.--Superiority of the female in most insect species.--Exceptions.--Numeric dimorphism.--Female hymenoptera.--Multiplicity of her activities.--Male's purely sexual rôle.--Dimorphism of ants and termites.--Grasshoppers and crickets.--Spiders.--Coleoptera.--Glow-worm.--Cochineal's strange dimorphism.

V. Sexual Dimorphism

2. Vertebrates:--Unnoticeable in fish, saurians, reptiles. --The bird world.--Dimorphism favourable to males: the oriole, pheasants, the ruff.--Peacocks and turkey-cocks. --Birds of paradise.--Moderate dimorphism of mammifers. --Effects of castration on dimorphism.

VI. Sexual Dimorphism

3. Vertebrates (Continued):--Man and woman.--Characteristics and limits of human dimorphism.--Effects of civilization. --Psychologic dimorphism.--The insect world and the human. --Modern dimorphism, basis of the pair.--Solidarity of the human pair.--Dimorphism and polygamy.--The pair favours the female.--Sexual æsthetics.--Causes of the superiority of feminine beauty.

VII. Sexual Dimorphism and Feminism

Inferiority and superiority of the female as shown in animal species.--Influence of feeding on the production of sexes. --The female would have sufficed.--Feminism absolute, and moderate.--Pipe-dreams: elimination of the male and human parthenogenesis.

VIII. Love-Organs

Sexual dimorphism and parallelism.--Sexual organs of man and of woman.--Constancy of sexual parallelism in the animal series.--External sexual organs of placentary mammifera. --Form and position of the penis.--The penial bone.--The clitoris.--The vagina.--The teats.--Forked prong of marsupials. --Sexual organs of reptiles.--Fish and birds with a penial organ.--Genital organs of arthropodes.--Attempt to classify animals according to the disposition, presence, absence of exterior organs for reproduction.

IX. The Mechanism of Love

1. Copulation: Vertebrates.--Its very numerous varieties and its specific fixity.--The apparent immorality of Nature. --Sexual ethnography.--Human mechanism.--Cavalage.--The form and duration of coupling in divers mammifers.--Aberrations of sexual surgery, the ampallang.--Pain as a bridle on sex. --Maidenhead.--The mole.--Passivity of the female.--The ovule, psychological figure of the female.--Mania of attributing human virtues to animals.--The modesty of elephants.--Coupling mechanism in whales, seals, tortoises.--In certain ophidians and in certain fish.

X. The Mechanism of Love

2. Copulation (Continued)--Arthropodes.--Scorpions.--Large aquatic crustaceans.--Small crustaceans.--The hydrachne. --Scutilary.--Cockchafer.--Butterflies.--Flies, etc.--Variation of animals' sexual habits.

XI. The Mechanism of Love p. 98

3. Of birds and fish.--Males without penis.--Coupling by simple contact.--Salacity of birds.--Copulation of batrachians: accoucheur toad, aquatic toad, earth toad, pipa toad.--Fœtal parasitism.--Chastity of fish.--Sexes separated in love. --Onanistic fecundation.--Cephalopodes, the spermatophore.

XII, The Mechanism of Love