MUSEUM OF COMPARATIVE ZOOLOGY. 141 
III The Ovarian Capsule. 
Plate II. Figs. 21-26. 
The epithelium of the ovarian capsule is not often easily made out in 
ordinary stained preparations, for the nuclei of muscle fibres and con- 
nective-tissue cells lie not only just external to the epithelial nuclei, 
but frequently in the same plane with them. In most of my prepara- 
tions the boundaries of the epithelial cells cannot be seen at all, and I 
have therefore confined my attention mainly to those which show them 
distinctly. In shape, the cells are more or less irregular, oblong hexa- 
gons (Figures 24 and 25 represent typical shapes). The cell walls are 
broad and fibrillated, like those of the serosa, though the cells them- 
selves are smaller even than those of the amnion. The nuclei are not 
only larger in proportion to the cells, but often larger absolutely, than 
the amniotic nuclei. The amount and arrangement of the chromatin 
in the capsular nuclei (except in a certain phase) is almost precisely 
like that already described for the nuclei of the amnion, but there is usu- 
ally only one conspicuous nucleolus. The small amount of chromatic 
substance, aside from the nucleolus, has a granular appearance, but 
sometimes shows indications of a filamentous or reticular arrangement 
(see Figs. 21, 23, 24). Seen in face view, the nuclei are circular, and 
have a distinct nuclear membrane. The section (Fig. 2, nl. fol.) shows 
that they are less flattened than the amniotic nuclei. 
Here, again, we have amitotic division, and of precisely the same 
type as prevails in the amnion, Apparently, division is not of common 
occurrence, for I have been able to find only a few instances, and have, 
Figures 21, 22, and 23 show 
unfortunately, not seen its earliest stages. 
As each daughter nucleus 
the simple manner in which it is effected. 
contains a nucleolus, and the ordinary resting nucleus has but one, 
division of the nucleolus must precede division of the nucleus. In one 
important respect the division of these nuclei differs from that of the 
amniotic nuclei, The cell does not divide immediately after the nucleus, 
and consequently a great number of cells are binucleate. Some even 
contain three nuclei. I have obtained no evidence whatever of cell 
division. 
