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Detailed cytological study in the tetrasomics of Coix gigantea Koen. ex Roxb. (Poaceae) has been carried out revealing a possibility of wider range in the gametic constitution than is generally predicted through breeding experiments. Although majority of the PMCs showed nine bivalents and a quadrivalent association at diakinesis, the four homologues gave two bivalents, bivalent and two univalents, trivalent and a univalent and rarely four univalents. Orientation and segregation in all these associations, especially irregularities involving quadrivalent and univalent, have resulted in gametes with from n=9 (n-1) to n=13 (n+3) chromosomes. There is every reason to believe that gametes up to n+2 (n=12) constitution are functional since polysomics, pentasomic (2n+3, 2n=23) and hexasomic (2n+4, 2n=24), have been isolated and cytologically studied by us in the past.