504 THE CYTOLOGY OF THE SUGARCANE 
right side of the figure two univalent chromosomes are seen, lying at 
some distance from each other, 
which have been drawn dark gray. 
The same can be seen just above the 
nucleolus. At the top of the figure 
an additional univalent chromosome 
(drawn dark gray also) is seen, which 
lacks a partner. A few other univa- 
lent chromosomes, but little conspi- 
cuous in the figure, did occur in ad- 
dition. In this case about 38 bivalent 
Fie: 6. and 13 univalent chromosomes were 
present, of the latter 10 were more 
Nucleus of a pollenmothercell of roo ; ‘ 
POJ in diakinesis. x 2300. or less conspicuously arranged in 
sets of two. 
In other diakinesis nuclei an approximately equal number of biva- 
lent and univalent chromosomes was seen; all counts pointed towards 
a diploid number of 88 or 89. 
Univalent chromosomes were always present but not always in the 

ge % © Bp® » same quantity. Fig. 7 pictures 
aos e$e © pe a case in which 89 chromosomes 
AL > . geo Boot could with certainty be counted. 
Py A 0, 28 The same number was found in 
5 be ae other anaphases, but occasion- 
Hig. ally but 86—88 chromosomes 
Anaphase of the heterotype division of were visible in less perfect prep- 
ee CCE el from one of the poles) x10 one, Doubtless 100 PO J has 
in the diploid phase 89 chrom- 
osomes, a number which corresponds exactly with the sum of the haploid 
chromosome-numbers of Bandjarmassin hitam (40) and Loethers (49). 
100 POJ forms normal pollen-tetrads. 
Koesoema (Derived from the cross Djamprok x Loethers). Koesoema 
cane always shows very irregular reduction-divisions. Counts in 
diakinesisnuclei were consequently impossible. Metaphases, viewed 
from the side, showed the irregularity especially well. Fig. 8 gives 
an example. In the case of regular divisions the gemini are situated 
pretty nearly in one plane during metaphase; they are more or less 
diamond-shaped or stretched lengthwise and laced, because the two 

