DR. MARTIN BARRY’S RESEARCHES IN EMBRYOLOGY. 
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sented a remarkable, opake nucleus (par. 342.). The space around these 
cells was occupied by larger cells, apparently undergoing liquefaction. 
50 diam. 
Fig. 171. A fecundated ovarian ovum of 8^ hours, and measuring in diameter yy"', 
from the same ovary as that in the preceding figure. It was apparently 
in a similar condition. It is not (as in fig. 170.) the surface, but the 
interior of the ovum that is here seen. The point of fecundation had 
now reached the centre of the germinal vesicle (c). (See the explana- 
tion of fig. 109.) 50 diam. (par. 341.) 
Fig. 172. A fecundated ovarian ovum of 8^ hours, and measuring in diameter only 
Yt'" (par. 365.). The cells under the membrane /'were circumscribed 
by a proper membrane (e), between which and the membrane f there 
was a space filled with transparent fluid (pars. 338. 339. 342. 343. 360.). 
The centre of the ovum was occupied by the germinal vesicle, around 
which were large, regularly elliptical, and flattened cells. These cells 
possibly corresponded to those occupying a similar situation in figs. 170 
and 171 : but they were in a more advanced state. 100 diam. 
Fig. 173. A fecundated ovarian ovum of six hours, and measuring in diameter yj". 
(Its Graafian vesicle was large.) This ovum differed from that of the 
preceding figure in having a layer of minute cells around the germinal 
vesicle (c), not observed in the ovum of the preceding figure. The mass 
of large cells external to these was surrounded by a proper membrane 
( e ) (pars. 338. 339. 342. 343. 360.). Immediately under the membrane 
/', were the remains of cells undergoing liquefaction. The membrane f 
still presented an orifice (par. 344.), not seen in the ovum fig. 172. (In 
the latter it had possibly closed) (par. 344.). At g l are the cells of the 
tunica granulosa, which had become elongated, and club-shaped, and 
were in contact with the membrane f by their pointed extremities alone 
(par. 345.). The tunica granulosa exhibited around the orifice, in the 
membrane f, a depression — apparently the effect of pressure towards 
the exterior of the ovary (par. 335.). 50 diam. 
Fig. 174. The same ovum in outline, on a larger scale ; the tunica granulosa being 
omitted. 100 diam. (pars. 344. 360.) 
Fig. 175. A superficial view of the same ovum as that in the two preceding figures. 
100 diam. (pars. 344. 360.) 
Fig. 176. A fecundated ovarian ovum of 8-j- hours, and measuring in diameter 
Yt'"-\-. It differed from the ovum fig. 175. in the following respects, 
namely : The cells apparently corresponding to those, the remains of 
which in the ovum fig. 175. were seen immediately under the membrane 
f, had entirely liquefied, leaving a transparent fluid in their place ; and 
cells possibly corresponding to the large ones which in the ovum fig. 
