Most of the viscera are innervated by the sympathetic system, and the visceral manifestations of emotion indicate the dominance of sympathetic impulses. “When, for example, a cat becomes frightened, the pupils dilate, the stomach and intestines are inhibited, the heart beats rapidly, the hairs of the back and tail stand erect—all signs of nervous discharge along sympathetic paths” (Cannon). Cannon and his co-workers have further made the acute suggestion that, as adrenalin itself is capable of working the effects evoked by sympathetic stimulation, “the persistence of the emotional state, after the exciting object has disappeared, can be explained” by the persistence of the adrenalin in the blood. There is reason to believe that some of the adrenal secretion set free by nervous stimulation returning in the blood stream to the glands stimulates them to further activity, and this would tend to continue the emotional effect after the emotion has subsided. “Indeed it was the lasting effect of excitement in digestive processes which suggested” to Cannon his investigations.[208] According to Féré[209] the _pupils_ may dilate under the influence of asthenic emotions and contract with sthenic emotions. However that may be, the dilatation of the pupils during states of fear may be demonstrated in animals. exert force of which he is ordinarily incapable. Or this energy, instead of being discharged into the channels being made use of by the will, and so augmenting its effects, may be so discharged as to inhibit the will, and produce paralysis of the will and muscular action. These muscular vasomotor and secretory changes need not surprise us, as indeed they have a biological meaning. As Sherrington[210] has pointed out, “there is a strong bond between emotion and muscular action. Emotion ‘moves’ us, hence the word itself. If developed in intensity, it impels toward vigorous movement. Every vigorous movement of the body ... involves also the less noticeable co-operation of the viscera, especially of the circulatory and respiratory [and, I would add, the secretory glands of the skin]. The extra demand made upon the muscles that move the frame involves a heightened action of the nutrient organs which supply to the muscles the material for their energy”; and also involves a heightened action of the sweat glands to maintain the thermic equilibrium. “We should expect,” Sherrington remarks, “visceral action to occur along with the muscular expression of emotion,” and we should expect, it may be added, that through this mechanism emotion should become integrated with vasomotor, secretory, and other visceral functions.