= Pee 
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. 1906] SCHAFFNER—LILIUM TIGRINUM 187 
uncoiled and pulled apart. They are separated at the closed outer end. 
A transverse splitting of the chromosome is thus accomplished. There 
is no evidence that the two limbs of the chromosome are a male and 
female chromosome joined end to end and twisted together until they 
make a longitudinal pair. But theoretically such a proposition is 
easily possible or even probable. Because the spindle threads are 
attached some distance from the ends of the limbs, the daughter chro- 
mosomes are developed as V- or U-shaped loops (jigs. 40, 43, 51).- In 
favorably stained sections some evidence of chromatin granules may 
be observed. These still show a distinct pairing in some cases (jig. 44), 
but in others the arrangement is considerably disturbed (jig. 45). 
The daughter chromosomes, as they appear in the daughter star, are 
of various forms and are sometimes twisted (figs. 44-50). 
The micronucleoli are gradually collected below the two daughter 
skeins, and are finally all inclosed in the nuclear cavities of the daugh- 
ter nuclei (figs. 52, 53). The daughter chromosomes do not appear 
to form a very definite resting network, but are transformed into the 
mother skein of the second division rather rapidly. Whether a con- 
tinuous ribbon is formed was not ascertained. The loops are already 
separate at an early stage, and it is possible that the daughter chro- 
mosomes of the first division, after forming an imperfect reticulum, 
break up directly into the twelve chromosomes of the second division 
(fg. 54). This point, however, is doubtful. But the absence of a defi- 
nite resting stage in sections having microsporocytes with loose daugh- 
ter skeins in close proximity to loose mother skeins of the second 
division, gives support to the above supposition. The micronucleoli 
are again distributed in the cytoplasm before the mother-star stage 
of the second division (figs. 54, 55). The karyokinetic figures of the 
second division are easily distinguishable from those of the first. 
This is especially true of the mother star (figs. 38, 55). The chro- 
mosomes in the second division have their free ends directed out- 
wards, as in an ordinary vegetative division. Commonly they are 
more or less tangential to the spindle. Sometimes, however, they 
Stand at right angles, as represented in jigs. 56, 57. 
One of the most difficult points to determine was the nature of the 
splitting in the second division. However, it was definitely ascer- 
tained that the splitting is longitudinal. Dividing chromosomes are 
