CELL-DIVISION IN THE SEX CELLS OF TAENIA 213 
the first without any intervening resting stage. In figure D are 
shown two cells in the metaphase of the second spermatocyte 
division while in figure C are shown two cells in the metaphase and 
two in the anaphase. In the late anaphase the chromatin is 
collected in a mass at the poles. Occasionally there is a small 
portion of éhromatin which lags behind the mass. This is illus- 
trated in 1 and 2 of figure E and 1 of figure F. The spindles are 
even more delicate than in the earlier anaphases and the meta- 
phase. I have seen no division of the centrosome. 
2. Oogonial divisions 
In the oogonial divisions mitoses are very frequent and there 
are no constricting nuclei nor nuclei in close contact. Plate 2 
shows oogonial cells in different stages of mitotic division. The 
spindle is very similar to the spindle in the spermatocyte divi- 
sions but the centrosome is different. Here the centrosome is 
globular in form (showing a circle in section), comparatively 
large and stains a little more deeply than the spindle fibers. No 
aster is present. Some parts of the cytoplasm staing a little 
more deeply than others, thus giving it a mottled appearance. 
In the so-called resting stage the nucleus is very large and con- 
tains a large nucleolus which usually lies to one side of the nucleus 
and stains like chromatin. The chromatin is more or less scat- 
tered through the nucleus as a finely granular reticulum. The 
nuclear membrane stains like the chromatin and chromatin gran- 
ules are distributed around the periphery of the nucleus. Figure 
E, plate 2, shows two oogonial cells in the resting stage and 
figure A, plate 3, shows one in the resting stage and the other 
in the telophase. The nuclear membrane has not yet formed, 
nor has the cell completely constricted. 
3. Synapsis and the growth period 
At the beginning of the growth period a marked change takes 
place in the appearance of the cells. There is a slight increase 
in the amount of the cytoplasm and a great increase in the mass 
of the chromatin. The chromatin takes the stain very readily 
