Abstract

Hybrids are known in 62 out of the 270 recognized genera of ferns and fern allies. To date 522 pteridophyte hybrids have been recorded in literature. The hybrids known to occur in 55 genera are discussed, out of 253 whose chromosomes were counted 29 were diploids, 129 were triploids, 76 tetarploids, 14 pentaploids and 5 hexaploids, in other words almost 90% were polyploids. Of the 255 spores studied 84% were sterile, but 16% were fertile.