Abstract: | Palmelloids induced in the unicellular green alga Chlamydomonas eugametos by chloroplatinic acid treatment have been studied electron microscopically. Thin-sectioned specimens revealed the multilayer nature of the cell walls after second division within the palmelloid. Although synchrony in cell division is lost, to a certain degree, within the palmelloid, the cells themselves appeared normal, and the presence of normal flagellar structure was confirmed. The presence of the eyespot was observed at the optical level as well as in the freeze-etched specimens. The above results support the hypothesis that the palmelloid condition of Chlamydomonas eugametos induced by chloroplatinic acid is due to an abnormality in cell wall formation rather than flagellar malfunction or loss. |