In all other cases, zoospores are uninucleate bodies.
In plants with multinucleate cells, such as Albugo, Peronospora and Vaucheria, it is usually a uninucleate cell differentiated by separation of the nuclei from a multinucleate cell, but in Albugo bliti it is multinucleate, and in Sphaero plea it may contain more than one nucleus.
The contents of the antheridium are not set free, but that organ penetrates the oogonium by means of a narrow outgrowth, the fertilizing tube, and a male nucleus then passes over into the single oosphere, which at first multinucleate becomes uninucleate before fertilization.
Fertilized egg with the central uninucleate cell (o) surrounded by the oosphere and the fertilizing periplasm (p).
Then by a special method, described first by Harper, a mass of protoplasm is cut out round each nucleus; thus eight uninucleate ascospores are formed by free-cell formation.