As I have already shown in a previous communication,[168] the lymphatic glands stand in very close relation to the thyroid gland. In diseased conditions of the thyroid we find, as a rule, enlarged lymphatic glands, as in Graves’s disease, myxœdema, cretinism, acromegaly, and also in diabetes. The thyroid seems to exert a great influence, not only upon the lymphatic glands, but also on the blood-corpuscles. The red blood-corpuscles are diminished after extirpation of the thyroid, as also in myxœdema, as well as in old age. On the other hand, they can be increased very considerably by thyroid feeding. The white blood-corpuscles are also influenced by the thyroid, for, after extirpation of the thyroid, their number is at first increased and later diminished. Very important is the discovery of Mlle. Fassin[169] (in the laboratory of the University of Liège, Belgium), who found a diminution in the production of alexins after extirpation of the thyroid, thus confirming what Sajous had pointed out four years earlier. According to Sir Almroth Wright, the discoverer of opsonins, the production of these bodies also depends upon the internal secretions. We have seen that Sajous has shown (a fact confirmed by others since) that opsonins are mainly composed of thyroid secretion. Footnote 168: Policlinique de Bruxelles, Avril, 1903. Footnote 169: Report in Centralblatt für Stoffwechsel, 1907. Thus we see that the production of antitoxins is greatly under the influence of the thyroid, which governs the processes of phagocytosis, and thus powerfully helps in the defense of our system. Besides microbes, we introduce into our body a large number of harmful products through food and drink (stimulants). Many toxic substances are formed by the decomposition of food, and also in the processes of metabolism in the tissues. We are protected against these substances by certain organs which destroy them (as the thyroid, parathyroids, and liver), and by other organs which eliminate them (as the kidneys, the skin, and the intestines). When these organs are all working well, we may get rid of these products and not be affected by them; but in old individuals it is different, as their protective and eliminative organs have more or less degenerated. Then these substances are not destroyed entirely, nor wholly eliminated. They are retained, and cause the condition of auto-intoxication.