On the Division of Macronucleus in the Living Gymnostome Ciliate, Chlamydodon pedarius with Special Reference to the Behaviors of Chromonemata, Nucleoli and Endosome

Abstract

The behaviors of chromonemata, nucleoli and endosome during the division of the macronucleus in the living Chiamydodon peclarius have been observed by the phase contrast microscopy.
1. The chromonemata have appeared at prophase with the extrusion of the nucleolar materials, which have been masking the chromonemata.
2. The chromonemata of the organism do not develop into usual chromosomes at metaphase, and their characters resemble the endornitotic chromosomes of Heteroptera and Drosophila.
3. The division apparatus including the polar caps and central substance, which are responsible for the chromonemata movement, is produced with the transition of the endosomal substance during metaphase to early anaphase.
4. The extrusion of the nucleolar materials takes place at prophase, late anaphase and telophase, and the diffusion of the peripheral substance of the metaphase macronucleus has observed.
5. The mechanism of the protrusion of the nucleolar materials has been discussed with emphasis upon the increasing of the nuclear materials at prophase and the change consequent upon it of the structure of the macronuclear membrane.