420 BOTANICAL GAZETTE [JUNE 
apparently unite end-to-end to form a dispireme (figs. 31, 32). 
The nucleus with the included spireme has originally the shape 
of the group of chromosomes in telophase, that is, a plate, and 
this is retained during the reconstruction stages. The spireme 
stains very densely at first (figs. 29-31) while it still retains all the 
chromatin, but later becomes so faint that it is difficult to see 
(fig. 32). The formation of the reticulum from the spireme cannot 
be followed with any great clearness on account of the small size 
of the parts. There is a reticulum formed (fig. 32) in some manner, 
however, and on it appear bodies which stain more densely than 
the meshwork by which they are surrounded. At first these bodies 
are small and numerous, but in the later stages (fig. 33) they have 
fused into masses of considerable size; these masses will later form 
the compound nucleolus. When the nucleus has been entirely 
reconstructed, these bodies still lie more or less scattered, and while 
the nucleus is making its way back to its new position (fig. 34) 
there are still usually at least two groups. Apparently it is only 
after it has come to rest at the middle of the daughter cell that all 
of these nucleolar bodies take their position at the center of the 
nucleus. The process, as will be seen from fig. 35, 15 essentially 
the same in C. moniliferum as in C. Ehrenbergii from which the 
other figures were drawn. In C. Ehrenbergii there is only a slight 
fusion in places, while in C. moniliferum it is sufficiently complete 
to make a fairly homogeneous structure. 
After the nuclei have been reconstructed, they begin to move 
out to the surface of the cell (fig. 34) and then around the chromato- 
phore. The chromatophore being evidently a very dense structure, 
it is apparently much easier to go around than to penetrate it. 
In Spirogyra the central part of the cell is almost entirely free from 
cytoplasm, and the daughter nuclei would meet no such obstruc 
tion. As previously noted, this migration occurs along the ash 
of the chromatophore (fig. 7), where, as has been shown 1” ioe 
paper (27) on the chromatophore, there are fewer strands ° 
cytoplasm to impede its passage. . 
As the nucleus in both species usually arrives at the new Lee 
tion some time before the chromatophore has finished its die 
it is very common to find figures like nos. 6, 8, 11, and 39, in whic 
