264 BOTANICAL GAZETTE [SEPTEMBER 
near the poles of the spindle. Figs. 11, 12, and 13 represent the 
3 sections of this spindle, and in fig. 14 the 3 drawings are 
superimposed and slightly diagrammed. Of the 24 chromosomes 
present on the equatorial plate, 12 are contributed by the male 
nucleus and 12 by the egg nucleus. The chromosomes are not 
drawn into the sharp U’s and (C’s so characteristic of divisions in 
Lilium. The chromosomes come together in pairs in which they 
twist more or less about each other (fig. 12a). Each of the chromo- 
somes of the 12 pairs then breaks transversely at the center of the 
ellipse it forms, each pair giving rise to 4 segments. The 48 seg- 
ments in the form of small rods remain paired (fig. 120, c) as they 
move toward the poles of the spindle. The components of each 
pair are similar in size so far as could be determined; one segment 
is male and the other female in origin. In fig. 14 the 12 pairs of 
chromosomes are represented, with the 4 segments of a pair indi- 
cated by the same numbet. All segments going to one pole are in 
black, those to the opposite pole in outline. Chromosomes 8 and 
12 have not as yet come in contact and the transverse break has 
not yet appeared. This behavior of chromosomes resembles that 
of the first reduction division in tetrad formation. There is a 
pairing of chromosomes and a subsequent transverse breaking. 
The result of the division is not the reduced number of chromosomes, 
however, but the diploid number, for only a transverse break occurs, 
and no further splitting. 
In the telophase of this division (figs. 15, 16) no further evidence 
of the pairing of the chromosomes could be observed. It would 
seem probable that the individuality of the chromosomes derived 
from the male and egg nuclei would persist. The second division 
(fig. 17) of the fertilized egg is in all respects like the ordinary vege- 
tative division in Lilium, with a longitudinal splitting of the 
characteristic U-shaped chromosomes during the metaphase. 
Observations were also made on the behavior of the chromatin 
during triple fusion. The process occurs much more rapidly and the 
resulting nucleus divides at least twice before the fertilized egg 
undergoes division. At the time that the endosperm nucleus 
divides (fig. 7) the male and egg nuclei are still in the stage shown in 
fig. 3 or 4. The 2 polar nuclei, with membranes distinct, are in the 
resting condition when the male nucleus in the spireme stage comes 
