-DDT administered orally to cows, sheep, and horses at the rate of 100 mg. per kg. of body wt. during the first week, 150 mg. during the 2d week, and 200 mg. during the 3d week gave results indicating that DDT was not acutely toxic; that the nervous system is likely to be affected, although there appears to be a marked variation between spp. and between individuals of the same species in their susceptibility to DDT; that most of the DDT evidently is eliminated, although in one instance the blood of a DDT-fed animal was toxic to flies. There is usually a marked loss of appetite, and hemorrhages are frequently produced in the heart and in the lining of the intestines.