The Distribution of Chromosomes in the Pollen-Grains of a Triploid Hyacinth

(1) The pollen-grains of a diploid (or double diploid) clone of hyacinth showed two pairs of long V-shaped chromosomes with a median constriction; one pair of shorter J-shaped chromosomes with a subterminal constriction; and one pair of short chromosomes, also with a subterminal constriction. The presence of a number of pairs of chromosomes, the members of each pair being apparently identical, is characteristic of the pollen of tetraploid plants. (2) The pollen-grains of a triploid (or double triploid) done of hyacinth showed a number of chromosomes ranging from 8 to over 14. These belonged to the same size classes as those of the former done. (3) The extra chromosomes in the pollen of the triploid hyacinth which were in excess of the numbers in the pollen-grains of the diploid hyacinth, were distributed, collectively and in each size class, according to the laws of chance, after allowing for a source of slight error.