Abstract
Genetic stabilisation of diploid-like meiosis occurs in hexaploid, octoploid and decaploid taxa of Chrysanthemum. This stabilisation is ineffective in F1-hybrids between diploids and the several polyploids which have been obtained by ovary culture. The suppression of multivalent formation is effective in even-ploid hybrids although they are amphihaploid. A significant frequency of trivalents occurs in odd-ploid hybrids.
