Differentiation of Cells of the Rana pipiens Gastrula in Unconditioned Medium1

ABSTRACT A method has been devised for the culture of gastrular cells of R. pipiens. Histological and functional differentiation of nerve, muscle, and pigment cells is described as well as the differentiation of ciliated, mucus-secreting, and notochord cells. The inner layer of the presumptive epidermis differentiates into nerve-cells, ciliated cells, and ‘giant’ cells, in addition to an unidentified cell type X. Brief lithium treatment of presumptive epidermis results in a permanent transformation into pigment cells and mesenchyme.