Fine Structure of Chromosomes in the Mitotic Prophase of Ascites Tumour Cells

A COMPLEX, linear structure along the axis of certain meiotic prophase chromosomes has been observed in several animal spermatocytes 1–5 . Such structure has never been detected in mitosis or other stages of meiosis. The present communication is concerned with an electron microscope study of prophase chromosomes of ascites tumour cells, in which an axial structure of the chromosomes has been revealed. Ascites tumour cells, Ehrlich ascites tumour cells and Yoshida sarcoma cells have been examined by the electron microscope following conventional osmium fixation and methacrylate or epoxy resin embedding.