| Abstract: | Chloral hydrate [3.5 × 10?2 M] applied to archegonium of Marsilea vestila during oogenesis modifies the asymmetry of the gametic mitoses and the nuclear migrations. Multinucleate female gametes are obtained whose polarity is disturbed. At the ultrastructural level, the distribution of the organelles is changed profoundly. The ‘fertilization cone’ disappears, and there is increased vacuolation associated with myelin figures in the cytoplasm and the appearance of filament bundles. The nuclei also contain vacuoles and myelin figures. |
