“Grounds that will never be shaken” 256 XII. THE EXPRESSION OF THE EMOTIONS IN MAN AND OTHER ANIMALS. The Principle of Associated Habit 258 The Principle of Antithesis 261 Origin of the Principle of Antithesis 263 The Principle of the Action of the Excited Nervous System on the Body 265 XIII. MEANS OF THE EXPRESSION OF THE EMOTIONS. Vocal Organs 268 Erection of the Hair 269 Erection of the Ears 270 A Startled Horse 271 Monkey-Shines 271 Weeping of Man and Brute 272 The Grief-Muscles 275 Voluntary Power over the Grief-Muscles 276 “Down in the Mouth” 278 Laughter 279 Expression of the Devout Emotions 282 Frowning 284 Pouting 285 Decision at the Mouth 287 Anger 287 Sneering 288 Disgust 289 Shrugging the Shoulders 290 Blushing 291 Blushing not necessarily an Expression of Guilt 293 Blushing accounted for 294 A New Argument for a Single Parent-Stock 296 XIV. THE PROVISIONAL HYPOTHESIS OF PANGENESIS. Functional Independence of the Units of the Body 299 Necessary Assumptions 302 Two Objections answered 305 Effect of Morbid Action 306 Transmission limited 307 XV. OBJECTIONS TO THE THEORY OF DESCENT WITH MODIFICATION CONSIDERED. Misrepresentations corrected 310 Lapse of Time and Extent of Area 311 Why the Higher Forms have not supplanted the Lower 313 The Amount of Life must have a Limit 316