Slide showing six diagrams labelled A to F demonstrating 'the main stages of mitosis'. Slide shows six diagrams labelled A to F demonstrating 'the main stages of mitosis'. Title below diagrams reads: 'Fig 2 - diagrams of the main stages of mitosis. Only two pairs of chromosomes A and A', and B and B' are shown. Both of these have sub-terminal spindle attachments, those of the B chromosomes being nearer the end. At early prophase the "relic spirals" are clearly seen. S.A = spindle attachments, E.P. = equatorial plane of the spindle. R.L. are regions of the chromosomes which are spiralised in a right or left handed direction at metaphase.' Late 19th to early 20th century