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DR. MARTIN BARRY’S RESEARCHES IN EMBRYOLOGY. 
175. entered into the formation of the central mass, appeared in their 
turn to be undergoing liquefaction, but were still circumscribed by a 
membrane ( e ) (pars. 338. 339. 342. 343. 360.) ; while another set of cells, 
perhaps corresponding to the minute ones surrounding the germinal 
vesicle ( c ) in the ovum figs. 173. (174. 175.), had become very large. 
100 diain. 
Fig. 177- Section showing the structure of one of the compound discs of which the 
.substance surrounding the germinal vesicle in some states consists ; a 
structure which appears to be essentially the same — differing only in 
degree — in all the compound discs met with in the evolution of the 
ovum. This figure is for the most part in outline. 300 diam. (pars. 33/. 
382. 383.) 
Fig. 178. A fecundated ovarian ovum of nine hours, and measuring in diameter 
yJ" . Immediately under the membrane f — and without a proper in- 
vesting membrane (pars. 338. 339. 342. 343. 360.) — were large cells, 
filled with the foundations of other cells ; the latter in concentric layers 
surrounding a pellucid point. 100 diam. 
Fig. 179. A fecundated ovum of nine hours, and measuring in diameter about X 2 '". 
It was taken from the same ovary as the ovum in the preceding figure. 
The cells under the membrane f — without a proper investing mem 
brane (pars. 338. 339. 342. 343. 360.) — were even larger than those in 
fig. 178, presented minuter cells between them (par. 351.), and were 
undergoing liquefaction. The point of fecundation was seen in the 
centre of this ovum. 50 diain. 
Fig. 180. Another fecundated ovarian ovum of nine hours, and measuring in dia- 
meter Tt'", from the same Rabbit as the ova in figs. 178 and 179. The 
large cells under the membrane /"were not circumscribed by a proper 
membrane, and seemed to be undergoing liquefaction (pars. 338. 339. 
342. 343. 360.). 50 diam. 
Fig. 181. A fecundated ovarian ovum of ten hours, and measuring in diameter xj'". 
The substance under the membrane f seemed to be invested by a proper 
membrane, e (pars. 338. 339. 342. 343. 360.). This figure represents the 
cells of the tunica granulosa (g 1 ) in their altered, club-like form. Each 
of these cells, at this period, is in contact with the membrane/' by its 
pointed extremity alone (par. 345.). 100 diam. 
PLATE XXIV. 
All the Figures are from the Rahhi.t ( Lepus Cuniculus , Linn.), except Jig. 183. 
Figs. 182. 183 and 184, are copies of all the delineations of ova from the Fallopian 
