Cytoplasmic flow between stained and unstained hyphae in wild-type N. crassa.

The left panel is a pseudo-bright field and the right panel is a fluorescent confocal channel. The flow of unstained cytoplasm replacing stained cytoplasm is quick and very dramatic after the fusion pore becomes open. Note that the apex of the hypha is swollen and that there is no indication of peg formation on the stained hypha.