Fig. 11. Chromosomes of cells in the stage shown in figure 10. These represent the different types of rings, crosses, etc., commonly observed in first spermatocytes just before the formation of the mitotic figure.
Fig. 12. Different forms assumed by the accessory chromosome in the prophase of the first spermatocytes of Xiphidium.
Fig. 13. Metaphase of the first spermatocyte. The accessory chromosome is seen at one pole of the spindle, to which it has moved before the separation of the chromatids of the remaining chromosomes.
Fig. 14. Another cell in about the same stage as that represented in the preceding figure.
Fig. 15. A first spermatocyte metaphase in which the accessory chromosome has not as yet moved to the pole of the spindle. This is uncommon in Orchesticus, but frequent in Anabrus.
Fig. 16. Pole view of a first spermatocyte metaphase, showing seventeen chromosomes. The variation in size of the elements, so marked in the spermatogonia, is even more pronounced here. This is a cell similar to that of figure 15, in which the accessory chromosome lies in the equatorial plate.
Explanation of Plate VIII.
Fig. 17. Two cells in metaphase—a pole view of one and an oblique view of the other. The accessory chromosome does not show in the former, the cell being such a one as is represented in figures 14 and 15.
Fig. 18. Pole view of another cell, showing but sixteen chromosomes.