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Summary and Conclusions 1.The morphological characters of several allotetraploids (2n=28) have been described. All of them are perennial.2.In the mitosis no marked difference was noted in the Karytotypes of the allotetraploid.3.The meiosis of all the allotetraploids plants derived from back crossing the allohexaploid with the diploid was in the main similar. They all gave trivalents at diakinesis. In the plant derived in the F2 progeny, however, quadrivalents were noted.4.The hypothetical genomic make up of these plants has been presented. Inspite of the increase in the genomes of the cultivated plant the allotetraploids showed greater resemblance to the wild than to the cultivated ones. The plants are rust resistant under field conditions.

Summary 1.The morphological characteristics of the colchicine induced amphidiploid of the interspecific hybrid betweenP. typhoides andP. purpureum is described.2.The comparative study of the amphidiploid and its immediate parent the F1, did not show any marked differences either in the phenotypical characters except for the size of the stomata and pollen grains, higher fertility of the pollen and seed setting or in its chemical composition.3.The somatic counts gave 2n=42, the karyotype being similar in all respects with that of the F1.4.In meiosis only bivalents are formed inspite of the duplication of the chromosomes. At anaphase-I and-II disjunction bridges and fragmentation of chromosomes are met with. Despite the disturbed meiosis the tetrad formation is highly regular and viable pollen is formed.5.The behaviour of this amphidiploid is discussed in reference toP. pratense with which it is analogous in behaviour and found to corroborate the conclusion drawn there on.6.The plant conforms to the type of an Autoallopolyploid.