Sugar is the form in which carbohydrate material is transported in organisms; starch is the storage form. In the bodies of animals that have been well fed the liver contains an abundance of glycogen or “animal starch,” which may be called upon in times of need. At such times the glycogen is changed, and set free in the blood as sugar. Ordinarily there is a small percentage of sugar in the blood--from 0.06 to 0.1 per cent. When only this small amount is present the kidneys are capable of preventing its escape in any noteworthy amount. If the percentage rises to the neighborhood of 0.2-0.3 per cent, however, the sugar passes the obstacle set up by the kidneys, and is readily demonstrable in the urine by ordinary tests. The condition of “glycosuria,” therefore, may properly be considered, in certain circumstances, as evidence of increased sugar in the blood. The injection of adrenin can liberate sugar from the liver to such an extent that glycosuria results. Does the adrenal secretion discharged in pain and strong emotional excitement play a rôle in producing glycosuria under such conditions? In clinical literature scattered suggestions are to be found that conditions giving rise to emotional states may be the occasion also of more or less permanent glycosuria. Great grief and prolonged anxiety during a momentous crisis have been regarded as causes of individual instances of diabetes, and anger or fright has been followed by an increase in the sugar excreted by persons who already have the disease. Kleen[47] cites the instance of a German officer whose diabetes and whose Iron Cross for valor both came from a stressful experience in the Franco-Prussian War. The onset of the disease in a man directly after his wife was discovered in adultery is described by Naunyn;[48] and this author also mentions two cases in his own practice--one started during the bombardment of Strassburg (1870), the other started a few days after a companion had shot himself. In cases of mental disease, also, states of depression have been described accompanied by sugar in the urine. Schultze[49] has reported that in these cases the amount of glycosuria is dependent on the degree of depression, and that the greatest excretion of sugar occurs in the fear-psychoses. Raimann[50] has reported that in both melancholia and mania the assimilation limit of sugar may be lowered. Similar results in the insane have recently been presented by Mita,[51] and by Folin and Denis.[52] The latter investigators found glycosuria in 12 per cent of 192 insane patients, most of whom suffered from depression, apprehension, or excitement. And Arndt[53] has observed glycosuria appearing and disappearing as alcoholic delirium appeared and disappeared in his patients.