Abstract
Protoplasts from mesophyll cells from leaves of Nicotiana tabacum and cultured cells of Rauwolfia serpentina were used. When polyethylene glycol was added to a mixture of these protoplasts, some protoplasts phagocytotically ingested another whole protoplast into their vacuoles. Phagocytosis occurred not only between protoplasts of the same species but also between those of different species. At the initial contact of two protoplasts, the cytoplasm between the plasma membrane and the tonoplast of the ingesting protoplast migrated from the area of contact and an invagination developed containing the other protoplast which was finally incorporated into the vacuole by closure of the invagination.
