Lewis. — The Life History of Grijfithsici Bornetiana . 667 
which becomes the nucleolus of the daughter-nucleus. When the original 
nuclear membrane persists, the organization of the daughter nuclei is 
complete on the separation of the two halves of the nucleus, by which time 
no trace of the spindle is seen. When, as is more usual, the nuclear 
membrane disappears toward telophase, the mass of chromatin in the 
immediate vicinity of the kinoplasmic cap becomes surrounded by a new 
nuclear membrane, around which the kinoplasm becomes distributed. 
In any event, two daughter-nuclei are formed, which lie at some 
distance from each other. Each has a large, spherical, uniformly staining 
nucleolus in the centre, and frequently with two or three smaller bodies of 
chromatin in the nuclear cavity (Fig. 123). The daughter-nuclei are con- 
siderably smaller than the nucleus of the mother-cell. Each is about 5 ^ 
long by 6 ix broad, though the size varies. No trace of any partition has 
been observed between the daughter-nuclei, which lie quite freely in the 
cytoplasm. 
The daughter-nuclei do not remain long in the resting condition. In 
each the nucleolus disappears, and seven rounded chromosomes, probably 
derived from the nucleolus, appear in the nuclear cavity (Fig. 124). At 
the same time the nucleus elongates further, and there is to be seen a 
kinoplasmic cap at each end. A spindle is organized as before, and the 
seven chromosomes arrange themselves in an equatorial plate. The division 
of the two nuclei is synchronous, their axes of division lying at right angles 
to each other (Fig. 125). At anaphase, two groups of seven chromosomes 
pass to the poles of each spindle, the nuclear membranes disappearing 
(Fig. 126). At telophase the chromosomes of each group which are in close 
proximity to the kinoplasmic cap, fuse to form the nucleolus of the daughter- 
nucleus. A new nuclear membrame is formed around each mass of 
chromatin and the kinoplasm again becomes distributed around the nucleus. 
The four nuclei thus formed lie very near the periphery of the mother- 
cell, and equidistant from one another (Fig. 107). Each is a definitive 
tetraspore nucleus. Their arrangement in the cell is determined by the 
fact that one nucleus always lies at the point from which the cytoplasmic 
strand passes to meet the stalk-cell. The structure of the nucleolus at this 
stage is somewhat different from that of the preceding stages. The 
chromatin mass is usually plainly lobulated. Outside and near this is to be 
seen a much smaller, regularly spherical body, whose history I have been 
unable to trace. Probably it is of the same nature as the nucleolus, since, 
when the nucleolus fragments, as it does a little later, the smaller body is 
indistinguishable from the other chromatin masses. 
An appearance frequently seen at this stage lends support to the view 
that food material is passed up from below into the tetrasporangium (see 
Yamanouchi, 93 , p. 424). The nucleus which lies near the strand of 
cytoplasm connecting the tetrasporangium with the stalk-cell is seen to be 
