Health, adaptation to environment necessary for, 149 Health, ideal of, 148 Health, importance of, in relation to marriage, 135, 168, 171 _Hearn, Professor_, 67 Hedonism, New, 48 Hereditary tastes of children, 204 _et seq._ Heredities, antagonistic, of two parents, 58 Heredity among Flat-head Indians, 213 Heredity, definition of, 100 Heredity and education, 111 _et seq._ Heredity, evils arising from, may be cured, 35 Heredity, exceptions to law of, 58 Heredity and germ plasm, 107 Heredity, importance of knowledge of, by teachers, 125 Heredity, modification of law of, 99 Heredity, preponderating influence of, 69, 89 Heredity, rational view of, 109 Heredity, spectre of, 127 _et seq._ Heredity, theories of, 73 _et seq._ Heredity, transformation of, 83 _Hering, Richard_, 70 Hidery tribes of British Columbia, 214 High-pressure, effects of living at, 152 Hypnotic sleep, differs from ordinary sleep only in degree, 223 Hypnotic suggestion, value of, as aid to education, 216 Hypnotism as suggestive therapeutics, 214 Horse, evolution of the, 102 Human selection, plans for, 135 _et seq._ Human kind, regarded as a whole, should be benefited by our conduct, 211 Human race, further improvement of impossible, if marriage relation be regarded only from standpoint of sexual indulgence, 210 Humane sentiments, conflict of, with theories of evolution, 145 _et seq._ Husband and wife, tendency to resemble each other, 89 _Huth, A. H._, 42 Hygiene, modern, as opposed to natural selection, 142 _et seq._ Hygiene, as the ethics of the body, 160 Hygiene, promises of, 158 _et seq._ Hygienic laws, punishment for infraction of, 161 Hygienic surroundings, importance of, 139 Hygienic training, value of, 151 Ideal of Health, 148 Idiots, education of, 25 Illustrative cases of prenatal influence, 60 _et seq._ Imagination, effect of, on unborn offspring, 55 _et seq._ Improvement of race. See _race improvement_. Incas of Peru, consanguineous marriages among the, 23 Income, bodily, importance of living within, 152 Individual, the, as the beginning and end of the race, 50 Individuality, development of the, 126 Infanticide among Spartans, 15 Infanticide, former general prevalence of, 19 Infanticide in Plato's Republic, 11 Infanticide not morally permissible, 24 Inheritance of acquired characters, question as to the, 71, 73, 77, 79, 90, 109, 111 _et seq._ Inheritance, organic, wonders of, 101 Injuries during life, transmission of, 79 _et seq._ Injury to health through flattening the skull, 214 Instinct, explanations of origin of, 121 Instincts of the race for children, loss of, 208 Instruction and education, difference between, 210 Intelligence affected by head flattening, 214 Jacob, rods of, 56 _Jeune, Lady Mary_, 47 _Jowett, Professor B._, 25 _et seq._, 34