Abstract
1. In this present report, the result of cytological studies on the maturation division of PMC's of 6 interspecific hybrids *(ScxSV, SVxSc, Scx Sm, Sm X Sc, Sc x Sa, Sa X Sc) in genus Secale has been surnmerized. 2. In every combination, at the heterotyphase metaphase in PMC's of Fl plant, 5-7 bivalents and 0-4 univalents were observed. The freque, ncy of bivalents and univalents in the PMC's were shown in Table 1, and as shown in the Tabie the case of 7 in the number of bivalents appeared to be the mode. 3. Tri-, tetra-and pentavalents were rarely observed besides bivalents at the heterotypic metaphase.
