Consciousness, relation of to bodily functions, 160 Credé, on prevention of infantile blindness, 210 Cruger, on bees and orchids, 23 Cuisine, modern, evils of, 292 Cytotoxic serums, 245 Dahlmann, on meaning of Nirvâna, 156 Darwin, on fertilisation of orchids, 21, 22 on luminous insects, 37 on natural morality, 8 on origin of man, 40 Davids, Rhys, on meaning of Nirvâna, 156, 157 Death, Aurelius on, 262 Baudelaire on, 288 Cicero on, 169, 263 Guyau on, 195 Hartmann on, 184 Mailaender on, 188, 189, 190 Nordau on, 193 Plato on, 166, 167 Renan on, 195 Rückert on, 195 Schiller on, 195 Schopenhauer on, 179, 180, 181, 288 Seneca on, 171 Socrates on, 166, 167 Tokarsky on, 125 Tolstoi on, 122, 123, 299 Weismann on, 266 Zola on, 226 Philosophers on, 133 as annihilation, 162 compared with anæsthetics, 159 fear of, 115, 116, 153 feigning of, 114 in ephemerids, 275 instinct of, 281, 298 of Jewish patriarchs, 280, 281 natural, 266, 272, 277, 278, 279, 280, 299 in old age, 267 scientific study of, 262 Degeneration, senile, in infusoria, 231 in insects, 232 in vertebrates, 232 De Goncourt, quotations from, 121, 225 Deniker, a fœtus of man and ape, 47 Descartes, on lengthening life, 257 Desire of life, not to be ignored, 228 De Vries, on new species, 57 Diet, as regulated by religious, 162 Digestive system of man, 60 Disease, religious measures against, 164 Dogs, old age in, 233 D’Holbach, on natural morality, 7 Dragon-tree, of Oratava, 265 Dubois, on _Pithecanthropus_, 50 Du Bois Reymond, on agnosticism, 221 Dufour, on wasps, 27 Duhring, a blind optimist, 117 Duncan, Matthews, on childbirth, 94 Duration of life, 277, 278 Ebstein, on prolonging life, 258, 260 Ecclesiastes, on life, 293 Edgren, on arterial sclerosis, 247 Elixirs of life, 257 Emasculation, by Skoptsy, 9 Ephemerids (figures), 271, 273 absence of instinct of preservation in, 275 larvæ (figure), 272 sexual instincts of, 36 swarming of, 271 Epicureans, _summum bonum_ of, 6 Ewald, on microbes in intestines, 251, 252 Eye, of man, imperfections of, 78 Fabre, on caterpillars, 33 on fossorial wasps, 27, 28, 34 Faith, modern return to, 222 Tolstoi’s return to, 224 Zola’s attraction to, 225 Family instincts, 108 love, 295 Fauvel, on natural death, 280 Fear, of death, Rousseau on, 118 Tokarsky on, 125 Tolstoi on, 122, 123 in the aged, 118, 131 in Buddhism, 119 by a Christian minister, 124 by French writers, 121, 122, 132 instinctive nature of, 127, 128, 153 occasional absence of, 152 Feet, of man and apes, 43 Fichte, on future life, 176 Finot, on continuity of life, 197 on fear of death, 122, 126, 197 Flies, cause of death of, 274 Flora of the intestines, 248, 249, 251 Flourens, on limits of life, 277 Fœtus of gibbon, figure of, 46 of man, figure of, 47