
ES 




THE CYTOLOGY OF THE SUGARCANE 503 
THE CULTIVATED KINDS 
SW3. (Derived from Bl. Ch x Batjan) In some diakinesis-nuclei 40 
gemini were seen. Sometimes the reduction-division was perfectly 
normal, but in the majority of cases a small number of univalent chro- 
mosomes occurred. In metaphase sometimes 40 chromosomes could 
be observed, but in most cases a few chromosomes more could be 
counted owing to the occurrences of univalent chromosomes besides 
the bivalent ones. 
In several anaphases 80 chromosomes were seen. In fig. 5 an ana- 
phase is pictured with 38 chromosomes in the upper and 42 in the lo- 
wer group. Probably some chromosomes, still on the aequator, have 
been pictured in the upper group, because the short distance between 
them and the latter did not allow me to ee 
differentiate them from those of the en oy 
upper group. The haploid number of og 
SW3 is consequently 40, the diploid ge itA 
one 80. oe 
SW 11 (Derived from the same cross 
as SW 3). Metaphase-counts, in the 
case of this cane, gave sometimes 40 ne MX 
chromosomes, sometimes some more, the poles. x 2300. 

TG. 5: 
owing to the presence of univalent 
ones. In 7 cases anaphase counts could be made. In five of these 80 
chromosomes were counted, while in two cases it was doubtfull whether 
80 or 81 were present. We may therefore be sure that the haploid 
number of this cane also is 40, the diploid one 80. 
DI 52 (Derived from Bl. Ch. x Batjan). But a few counts could be 
made in root-tips as no flowers were available. Because the chromo- 
somes in the roottips are always long and bended and close together, 
absolutely reliable counts are impossible. The counts showed however 
that the actual diploid number of DI 52 can not be far removed 
from 80. 
100 POJ (Probably derived from Bandy. hitam x Loethers). Pollen- 
mothercells of this cane showed in diakinesis a large number of bivalent 
and a smaller number of univalent chromosomes. Fig. 6 gives an exam- 
ple. At a high focus 4 univalent chromosomes were seen arranged in 
sets of two; these have been drawn black in the picture. At the 
