Vol. 7, 1921 
GENETICS: J. BELLING 
199 
formation of triads. Thus Wilson 9 observed that three small chromosomes 
in Metapodius were grouped into a triad in the first division, and separated 
so that two went to one pole and one to the other. Osawa 5 found in trip- 
loid mulberries that some of the single chromosomes might be attached 
to the dyads in the first division of the pollen-mother-cells. In one trip- 
loid Canna (and in a triploid Datura), however, I found that all the chro- 
mosomes regularly form triads in the prophase and metaphase of the first 
division, and pass, two and one, in a random manner, to either pole. 
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FIG. 2 
The assortment of the chromosomes in the pollen-mother-cells of a triploid Canna. 
(1) Prophase showing triads. One chromosome separated from its corresponding 
dyad. (2), (3), (4), and (5) metaphase and early anaphase groups. In (3), one chro- 
mosome has again separated from its two partners. (6), (7), (8), and (9) metaphase 
plates for the second divisions, with cell-wall between, showing, respectively, 14 + 13,. 
15 + 12, 11 + 16, and 17 + 10 chromosomes. 
In 1920 I grew 46 differently named clones and species of Canna, ob- 
tained, without particular selection, from three leading dealers of New 
York, Philadelphia, and Florida, and from the U. S. Department of 
Agriculture. The chromosomes of 31 of these were counted in the first 
or second divisions of the pollen-mother cells; about 250 groups being 
