Xenogamy (Greek xenos=stranger, gamos=marriage) is the transfer of pollen grains from the anther to the stigma of a different plant.
This is the only type of cross pollination which during pollination brings genetically different types of pollen grains to the stigma.
[1] The term xenogamy (along with geitonogamy and autogamy) was first suggested by Kerner in 1876.
[2] Cross-pollination involves the transfer of pollen grains from the flower of one plant to the stigma of the flower of another plant.
The main characteristics which facilitate cross-pollination are: