Studies of Mitosis and Meiosis in Comparison

IV. A contribution to the study of the origin of the “bouquet” and its formation

Abstract

1) In Tradescontia and Psilotum, results are obtained which indicate that the base of the bouquet corresponds with the distal region of the chromosomes, if there takes place no rotation of the nucleus before the bouquet formation.
2) In Psilotum, it is shown by the deplasmolysis experiments, that the part of the nuclear membrane at the base of the bouquet is physically weaker than the other parts of the membrane.
3) In Trillium, it is frequently observed that the bouquet figure is like a group of cytasters.
4) It is suggested that the bouquet arrangement of the chromosome threads originates in the chromosome arrangement in the preceding telophase, and that in the presentation of the pronounced polarized appearance of the bouquet certain conditions or phenomena such as the differential structure of the nuclear membrane or the fusion of the nucleoli are concerned, in association with the change in water relation in the nucleus in prophase.
The present investigation was carried out under the direction of Prof. KUWADA to whom the author wishes to take this opportunity of expressing his sincere thanks. The author's thanks are also due to Dr. SINKE who helped the author much in various ways.