496 
Max Morse 
the upper left hand portiou of the plate in figure 33) is a single 
compact body. In Order to distinguish this body from the plasmo- 
some, counts were made in Auerbach preparations, where the plas- 
mosome conld be readily distinguished from the other nuclear com- 
ponents, but it mav also nearly always be seen in the iron alum 
sections and easily recognized. For a time during the late anaphase 
and telophase the odd chromosome may be seen occupying a position 
on one side of the mass of ordinary chromosomes (fig. 34) in one of 
the daughter cells. During the late telophase (fig. 35), it retains its 
staining power and lies as a well marked chromosome in one of the 
daughter nuclei. There is, then, no time during the first mitosis that 
the odd chromosome is lost to view or where it may be confused 
with another body. There is, moreover, no chance of its being ex- 
truded from the nucleus, as Moore and Robinson (’04) describe. On 
the other hand, it persists through the following spermatocyte division 
as a true chromosome, maintaining its integrity as a characteristic 
cell component. 
c) The plasmosome. Throughout the metaphase and anaphase 
of the primary spermatocyte,. the plasmosome lies at the edge of the 
spindle or a little way out in the cytoplasm (figs. 25, 28, 34). It 
gradually stains less and less deeply, although the intensity of the 
stain varies with the dye used. The central vacuole is a ready mark 
by wliich it may be distinguished (fig. 34). The plasmosome may 
fragment during anaphase, the portions being distributed to the daughter 
cells (fig. 34). At other times, it remains as a single body, fragmen- 
tation occurring in the early secondary spermatocytes. It has not 
been observed to enter the nucleus of the telophase of the first di- 
vision, when the nuclear wall has been formed, but lies invariably 
out in the cytoplasm. During the stages represented in figures 29 to 
32, it is difficult to make it out in iron alum preparations, but after 
the Auerbach stain, it is easily traced. There is, therefore, no 
chance of confusing the plasmosome with any of the chromosomes 
during this mitosis. 
6. The seeond spermatocyte division. 
a) The ordinary chromosomes. Cysts are frequently met with 
in which one may find a complete series of stages through the seeond 
spermatocyte division, beginning with the telophase of the primary 
spermatocyte and euding with the metaphase of the seeond division. 
Consequently, there is no question as to the sequence of events. ln 
