Abstract
Summary Lipids from blood thromboplastin were identified by column chromatography and paper chromatography as inositol phosphatide, lecithin, sphingomyelin, phosphatidyl serine, phosphatidyl ethanolamine, and cholesterol. Despite wide variations in thromboplastic activity in 70 samples of blood thromboplastin, there was no change in the presence of any of the lipids.