Abstract
The somatic number of chromosomes has been determined in root-tip cells of various garden varieties of the polyanthus narcissus. The results obtained (including the results of my previous paper, 1929) are listed in the Japanese text p. 159 (Fig. 1a-g).
For the sake of convenience in description, I have named the four garden varieties of which the original name is doubtful, as follows:-“B20” (the first mentioned variety in the list), “B21” (the third variety in the list), “A22” (the fourth variety) and “B31” (the eighth variety). This nomenclature is based on BAKER'S classification. He has classified the polyanthus narcissus into three groups, “bicolores”, “albae”and “luteae”according to the difference in the colour of the collora (BAILEY 1917, p. 2112). By“B20”is meant here that the plant is one belonging to the“bicolores”type and has 20 chromosomes in its somatic cells. In like manner, the letters A and B in the other cases also indicate that the plant belonging to the group which has the corresponding initial in its name, and the number at the foot of the letters signifies the somatic number of chromosomes which the plant carries.
In the present paper some results of observation of the meiotic phases in the pollen mother cells of the varieties with 20, 22, 30 and 32 chromosomes (2n) respectively are given.
