__ The lenses of late mice embryos were planted in a culture medium of rat serum 1.5 parts, Tyrode soln 1 part, mouse embryo extract 1 part, and distilled water 1-2 drops per ml. If the capsules were intact the lenses survived unchanged for 10 days; if the capsules were ruptured the lens fibers and subcapsular epithelial cells were extruded with subsequent dissolution of the former and proliferation of the latter. In some of the epithelial cells an increase in the amt. of cytoplasm and a movement of the nucleus to one side occurred, an appearance similar to the 1st stage in the process of normal differentiation of a lens epithelial cell into a lens fiber.