SUMMARY: The precleavage mitotic division in Arcyria cinerea was intranuclear and involved no centrioles. The division was nearly synchronous throughout the sporangium although nuclei in the upper portion of the sporangium usually began to divide first. At metaphase nuclei were roughly spherical. Intranuclear spindle fibres were visible and appeared to terminate near the inner surface of the nuclear envelope. By telophase the nuclei were very elongated In late telophase the nuclear envelope broke first in the interzonal region and then at the poles. The reconstitution of the nuclear envelope appeared to involve remnants of the original envelope as well as small vesicular elements resembling short segments of rough endoplasmic reticulum. The chromosomal spindle fibres, as well as some interzonal fibres, usually persisted until the nuclear envelope was completely reconstituted around a daughter nucleus. The division was completed by the time spore cleavage began in the sporangium.
MCMANUSM. A.,
ROTHL. E.1968; Ultrastructure of the somatic nuclear division in the plasmodium of the myxomycete Clastoderma debaryanum.. Mycologia 60:426–436
RYSERU.1970; Die Ultrastruktur der Mitosekerne in den Plasmodien von Physarum polycephalum.. Zeitschrift fur Zellforschung und Microskopische Anatomie 110:108–130