Abstract
The course of the mitotic cell divisions was successively observed in living spermatocytes of the shield-bug, Graphosoma rubrolineatum, by phase microscopy with the application of a liquid paraffin culture technique.
Based on the relationship between the behavior of the chromosomes during division, and the shortening and elongation of the cell axis, the suggestion was made that the migration of the chromosomes to poles is to be due to the contraction of the spindle fibers (the chromosomal fibers).
