By resorting toin vitrotechnique in inducing apogamy and apospory, diploid (polyhaploid, 2n= 58) and octoploid (2n= 232) plants have been produced from the natural tetraploid (2n= 116)Pteris vittataL. The ameiotic behaviour of the apogamously induced diploid (polyhaploid) establishes this species to be a genomic allopolyploid. Four kinds of sporangia, 16-, 32-, and 64-spored and sporangia with unequal spores and sporads were produced on the same individual. This analysis has revealed how in one step the tetraploid could have been formed in nature from hybrid diploid. It is suggested that this approach could be useful in analyzing the true nature of other sexually reproducing polyploid fern taxa.