A study of Michel's film on meiosis in Psophus stridulus L

Abstract

1. 1. Chromosome separation and the changes in cell and spindle diameters have been measured in cinematographs of two primary and two secondary spermatocyte divisions in Psophus stridulus L. 2. 2. Both primary spermatocyte divisions showed an increase in transverse diameters of the cell and spindle at the beginning of chromosome separation. In one of these there was also a concomitant decrease in longitudinal diameters and an increase in cell volume. 3. 3. An analysis of chromosome movement to the poles gives a force function which is compatible with the hypothesis of a contractile mechanism.