Microfilament bundles in antheridial nuclei of Achlya ambisexualis E 87.

This is the first report of intranuclear microfilaments within gametangial nuclei of oömycetous fungi. Longitudinal sections of four to six microfilaments were frequently observed in meiotic antheridial nuclei of Achlya ambisexualis. Each microfilament measured approximately 7--10 nm in diameter. Spindle tubules (25 nm in diameter) were also observed within some of the nuclei possessing microfilaments.