Cytological investigations in
Helwingia rusciflora (=
japonica) were made by Dermen (1932) and Wanscher (1933a). According to the former author, the somatic number of chromosomes is 80, while the latter reported 72 and 144 as the somatic numbers in the materials obtained from the Copenhagen Botanic garden and the Edinburgh garden respectively.
The present writer observed 60 bivaleuts in the polar view of heterotypic metaphase in pollen mother cells of the male plants. The gemini are similar in size and shape (Fig. 2). In the side view of the hetorotypic metaphase, an unequal pair of chromosomes consisting of two members of different size was observed (Fig. 3), indicating sex chromosomes of the XY type.
抄録全体を表示