774 THOS. H. MONTGOMERY, JR. 
is no evidence that chromatin particles leave the nucleus in the 
region of the idiozome. 
At about the time the sphere arises in the spermatocytes the 
idiozome begins to disintegrate, whereby it becomes more coarsely 
granular and these granules become dispersed. Successive stages 
of this process are exhibited in figs. 35, 37, 39-41, 42-48, 50. 
During these changes the idiozome separates into two masses 
that, becoming smaller, move apart from each other to the right 
and left of the primary axis of the cell (figs. 39, 43-47), and finally 
come to lie near opposite sides of the nucleus (fig. 50). This 
movement, as we have seen, is probably associated with move- 
ments of centrioles, though the latter are not yet visible. In 
stages later than fig. 50 no remains of the idiozome are to be seen. 
During this time also the chromatin plate of the nucleus becomes 
disestablished, by the chromosome ends withdrawing from the 
nuclear membrane (figs. 42-47, 50). No idiozome body reappears 
in any later cell generation, nor is another chromatin plate 
established in the nucleus, which would show that the growth of 
the idiozome is determined by the chromatin plate. 
C. The spheres 
This noncommittal term is here used for two sets of structures, 
both independent of the idiozome, the one in the first spermato- 
cytes and the second in the spermatids. 
In the first spermatocytes a sphere (Sp) is first seen in the 
stages of figs. 36 and 37 about the time when the idiozome (id) 
begins to degenerate. This is a rounded body at the distal end 
of the cell, which at first may appear either darker or lighter than 
the idiozome, and may touch or be separated from the latter. It 
lies within a large cytoplasmic vacuole; indeed during the whole 
growth period the cytoplasm is markedly vacuolar. The sphere 
increases in size until it attains its maximum volume shown in 
figs. 36 to 48, after which it diminishes, becoming gradually paler 
in color and more difficult to see (figs. 49-54). It disappears 
right after the stages of figs. 55 and 57. Rather rarely two spheres 
