Hyperglycæmia is found in emotional states and may lead to temporary glycosuria even in normal persons, and it may exist with normal metabolism. It may be found in mental disorders with emotionalism and the mechanism of its production is by stimulation of the suprarenal glands causing hypersecretion of adrenalin, which circulates to the liver, where more glycogen is mobilised and in consequence more glycose is found in the peripheral blood. In this research Bang's modified method was used for the examination of the blood for glycose, and examinations were made before breakfast and $f34 hr., 1$f12 hrs., and 2$f14 hrs. after this meal which consisted of 100 grms. of bread and 200 c.c. of milk. In dementia præcox and epilepsy the blood sugar was found to be subnormal before and slightly above the normal after breakfast. In dementia paralytica and non-anxious melancholia the blood sugar was slightly above the normal before and considerably above the normal after breakfast; and in anxious melancholia the highest blood sugar content was found at all times. In amentia, anxious patients showed a great increase of blood sugar after breakfast as compared with non-anxious patients, and in mania a similar increase was present in real emotional states, but was absent in hypomaniacal forms in which the patient was only optimistic and cheerful.