34i 
Nemalion multi fidum, Ag. 
certain of the bodies seem to contract, bringing them together so that they 
fuse, and in this way the number is brought down to eight, each of which is 
a chromosome (Figs. 54, 6 2). The thread system appears to be gradually 
absorbed into the chromosomes and they finally lie free in the nucleoplasm. 
Each of the chromosomes can be assumed to have retained its autonomy 
throughout the resting period, and the history of prophase is merely one of 
condensation and separation. 
The chromosomes then become arranged to form the equatorial plate 
(Figs. 55, 56, 63, 64, 65). The spindle is intranuclear, and the nuclear 
membrane remains intact until the beginning of anaphase, when it quickly 
breaks down. At metaphase large, broad polar structures are conspicuously 
present at the tips of the spindles. The most striking feature of the meta- 
phase in the cystocarp is the retention of the nucleolus. Presenting a rather 
empty and disorganized appearance, it takes a position on the edge of the 
equatorial plate, outside of the spindle, and does not disappear until the 
breaking down of the nuclear membrane. Wolfe observed this condition, 
but interpreted it as an extrusion of chromatin material representing part 
of the nucleolus. The presence of the nucleolus at this stage seems to be 
a fairly constant feature in the cystocarp, but has not been observed in 
vegetative divisions, this constituting the only difference that I have noted 
between the cystocarpic and vegetative mitoses. 
The chromosomes split at the plate, and the daughter chromosomes, 
eight in number, pass to the poles (Figs. 57, 58). The whole of the 
chromatin content passing to each pole is organized into a chromatin 
nucleolus, around which a nuclear membrane is formed (Figs. 59, 60). 
The nucleus thus organized increases in size, and the nucleolus becomes 
suspended by several radiating fibrillae (Fig. 60). It can then be seen that 
material passes out of the nucleolus, and that this material becomes distri- 
buted in a definite reticulum characteristic of the typical resting nucleus. 
We note, therefore, that at first the nucleolus is truly a karyosome, con- 
taining the whole of the chromatin material of the nucleus. Later on, this 
chromatic material becomes gradually distributed as a network throughout 
the nucleus. Occasionally, during the resting period, the nucleolus divides 
into two daughter nucleoli, a condition which has been seen nowhere but in 
the cystocarp (Fig. 50). 
The chromosome number in all of the divisions of the cystocarp is 
clearly eight. Since Wolfe, however, concluded that the reduction .takes 
place with the development of the first-formed carpospore from each fila- 
ment, I have given particular attention to the condition at that stage. As 
may be seen from Figs. 61-66, however, the prophase and metaphase of 
this division differ in no way from those of previous mitoses in the cystocarp 
and the chromosome number is the same. The cystocarp of Nemalion , there- 
fore, is haploid throughout its history in agreement with that of Scinaia . 
