抄録
Cytological investigation on 46 taxa belonging to 43 species under 14 genera of South Indian Aspidiaceae has been carried out. Chromosomal variations such as hybridity, aneuploidy, polyploidy and supernumerary division following meiosis have been encountered, The occurrence of species complexes has been detected in Arachnoides aristata and Cyclosorus interruptus. Bolbitis quoyana, Diplazium silvaticum, Tectaria paleocnemoides and T. decurrens var. minor have been found to be natural hybrids and the possible origin of the former three species has been suggested. Fifty per cent of the total 46 taxa investigated was found to be polyploids. Aneuploid changes in chromosome number have been detected in Thelypteris and Dryopteris. The origin of the different basic numbers in the genus Thelypteris has been discussed. It has been inferred from the present investigation that cytological changes like hybridity, polyploidy and aneuploidy have played an important role in the evolution of the Aspidiaceous ferns in South India.
