*[Footnote: The name “adrenalin” is proprietary. “Epinephrin” and “adrenin” have been suggested as terms free from commercial suggestions. As _adrenin_ is shorter and more clearly related to the common adjectival form, _adrenal_, I have followed Schäfer in using _adrenin_ to designate the substance produced physiologically by the adrenal glands.] The adrenals are glands of internal secretion, i. e., like the thyroid, parathyroid, and pituitary glands, for example; they have no connection with the surface of the body, and they give out into the blood the material which they elaborate. The blood is carried away from each of them by the lumbo-adrenal vein which empties either into the renal vein or directly into the inferior vena cava just anterior to the openings of the renal veins. The adrenal glands are supplied by preganglionic fibres of the autonomic group,[28] shown in solid line in Fig. 1. This seems an exception to the general rule that gland cells have an outlying neurone between them and the neurones of the central nervous system. The medulla of the adrenal gland, however, is composed of modified nerve cells, and may therefore be regarded as offering exceptional conditions. The foregoing brief sketch of the organization of the autonomic system brings out a number of points that should be of importance as bearing on the nature of the emotions which manifest themselves in the operations of this system. Thus it is highly probable that the sympathetic division, because arranged for diffuse discharge, is likely to be brought into activity as a whole, whereas the sacral and cranial divisions, arranged for particular action on separate organs, may operate in parts. Also, because antagonisms exist between the middle and either end division of the autonomic, affective states may be classified according to their expression in the middle or an end division and these states would be, like the nerves, antagonistic in character. And finally, since the adrenal glands are innervated by autonomic fibres of the mid-division, and since adrenal secretion stimulates the same activities that are stimulated nervously by this division, it is possible that disturbances in the realm of the sympathetic, although initiated by nervous discharge, are automatically augmented and prolonged through chemical effects of the adrenal secretion. REFERENCES [Footnote 21: Cannon: The American Journal of Psychology, 1914, xxv, p. 257.] [Footnote 22: For a summary of his studies of the organization of the autonomic system, see Langley: Ergebnisse der Physiologie, Wiesbaden, 1903, ii², p. 818.] [Footnote 23: See Cannon: American Journal of Physiology, 1905, xiii, p. xxii.] [Footnote 24: See Sherrington: The Integrative Action of the Nervous System, New York, 1909, p. 19.] [Footnote 25: Langley and Anderson: Journal of Physiology, 1895, xix, see pp. 85, 122.] [Footnote 26: Sherrington: _Loc. cit._, p. 90.]