Oestriol metabolism by rat- and rabbit-liver slices. Isolation of 2-methoxyoestriol and 2-hydroxyestriol.

smaller particles but did not solubilize them. Much less gangliosides were extracted after ultrasonic treatment of homogenates containing nuclei. 5. The effect of added agents and various treatments to homogenates on the quantity of gangliosides extracted from particulate and supernatant fractions was studied. 6. Addition of protamine or histone completely prevented the extraction of gangliosides. 7. A comparison of the affinity of subcellular fractions for basic proteins with the content of gangliosides was made. The fractions containing most of the tissue gangliosides showed the greatest affinity for basic proteins except a fraction rich in myelin fragments. 8. The probable localization of gangliosides in cell membranes is discussed.