In a series ofSolanumhybrids (2n= 24) studied meiosis was either normal, with regular formation of twelve bivalents per PMC, or else ten bivalents and a multiple chromosome association were present. Generally, these multiple associations were in the form of rings or chains of four, occasionally substituted by a chain trivalent and a univalent. Chromosome segregation at anaphase I and II was regular 12:12. Despite this, all hybrids were infertile, pollen sterility often exceeding 95%. Only the partially fertile F1S. indicumvar.multifloraXS. integrifoliumproduced F2progeny. In these F2plants multiple chromosome associations were observed in a fairly high frequency although such associations were not encountered in the corresponding F1. It is suggested that multiple chromosome homoeologies followed by pairing and crossing over in the F1could have resulted in the production of chromosomal interchanges in the F2. Despite regular synapsis and exchange leading to bivalent formation, segregational events at meiosis lead to the production of non-functional gametes in the F1's since those gametes with reconstituted parental genomes are expected to be functional.