A form of sexual reproduction that is occasionally
demonstrated by the ciliates. Two organisms will join together at the oral
groove. The micronucleus of each will undergo meiosis, producing several cells.
All but two of these in each organism disintegrate. One of these haploid
micronuclei remains in each cell, while the other migrates into the other cell,
fusing with the stationary gamete. The new nucleus -- which is now diploid and
contains a new genetic combination -- goes through cell division producing a new
macronucleus and a new micronucleus.
