Cotton seed, and the press cake obtained in the manufacture of cotton-seed oil, contains a poisonous substance to which Withers and Carruth gave the name gossypol (21). The oil extracted from the seed either by pressing or by extraction with fat solvents is also toxic to animals because of the presence of this principle. Cooking of the meal or heating in the hot press method for extracting the oil causes a change in this substance which renders it no longer soluble in oil or ether. It therefore remains in the meal (22). While cotton-seed flour or meal is a valuable feeding-stuff in animal production, its use as a human food is not to be recommended because no assurance is yet offered that the toxicity of the products can be removed entirely. The same may be said of cotton-seed flour. It must be further studied before it can be recommended as human food.