BIOCHEMISTRY OF THE WGLYCERYL ETHERS consist of long chain aliphatic alcohols( 1) determinable by gas-liquid chromatography ( 3 ) .Several different samples of epidermal phosphatides were chromatographed on silicic acid impregnated paper ( 10). The following phosphatides were identified: phosphatidyl serine, phospha t idyl e thanolamine, phospha tidy1 choline, inositol phosphatide, phosphatidic acids and sphingomyelin along with other phosphatides. These same phosphatides together with plasmalogens have been found in human epidermis by Bloomstrand et aL ( 16) and by Gerstein ( 17).Summary. In a limited number of analyses the lipid composition of human male and female epidermis of extremities shows differences in that female epidermis has much more triglycerides than does the male epidermis while the latter has more cholesterol, ether eluate and phosphatides than does female epidermis. The fatty acid composition of the triglyceride fraction is characterized in part by containing about 73% unsaturated fatty acids while this figure for the phosphatides is 50%. The phosphatides contain 2 unsaturated acids with 20 carbons and small amounts of pentadecanoic, heptadecanoic, behenic, lignoceric acids as well as the more common fatty acids.1. Haahti, E., Scand.