198 BOTANICAL GAZETTE _ [MARCH 
In fig. 49, where the cell plate is nearly completed and the 
nuclear membranes are beginning to appear, the spireme coil is 
still to be traced. It is now seen to be composed of a double 
strand of granules which are connected with each other in pairs 
and with the adjacent strands by the linin. With the complete 
separation of the daughter nuclei by the cell plate these strands 
become finer and the grouping more indistinct, until finally all 
that can be discerned in the quiescent nucleus are the chromatin 
bodies in a network and the nucleoli. 
A review of all the changes of the chromatic figure is now in 
order. A comparison of the stages which led up to the forma- 
tion of the equatorial plate with stages extending from that point 
to the formation of the daughter nuclei shows that the first series 
represents a gradual growth of tetrads and their fusion to form 
chromosomes; these latter split, half passing to each pole and in 
its passage suffering disintegration into tetrads. The changes in 
the two series are identical, but take place in the reverse order. 
The conditions in fig. 2, a mother-cell preparing to divide, are 
directly comparable with those shown in the daughter nucleus 
represented in fig. 49. Similarly, jig. 14 is comparable with fg. 
45, and the chromosomes at one pole of the diaster in jig. 42 
with those in figs. 7 and 8. 
The following diagrams show the order in which the changes 
in the chromatic figure occur. 
3 2 8 ee 5 = 
: i : i- 
Diagrams illustrating the morphology of the chromatic substance during at 
nesis: the diagrams in the upper series represent end views of a portion 0 
thread; those in the lower series, side views. 
In reviewing the literature of the chromatic figure in plant 
cells, no account of such an origin, structure, and development 
as has just been described for Allium was found. The literature 
on the botanical side has been mainly concerned with contro- 
