DR. MARTIN BARRY’S RESEARCHES IN EMBRYOLOGY. 
581 
5^ hours, and taken from the ovary. The chorion ( cho .) had a diameter 
of y". The membrane f (to'") was unusually thick. This ovum was 
taken from the same Rabbit as the ova in figs. 203 and 205. 100 diam. 
. 203. An ovum of no less than fifty-two hours, and measuring found in the 
uterus with that in the preceding figure, and that in fig. 205. (See the 
remarks on development not keeping pace with locality and size, in the 
explanation of fig. 202.) The twin cells (bs, in length), constitu- 
ting the germ, though smaller than those in fig. 202, seemed on the 
point of being liberated by the liquefaction of the cells surrounding 
them, and that of an investing membrane. The nucleus in one of the 
twin cells appeared to be situated at the surface of that cell (par. 378.). 
100 diam. 
204. An ovum of 24^ hours, found in the Fallopian tube between its middle 
and the uterus. It measured in diameter about yj". The incipient 
chorion (cho.) had begun to imbibe fluid and to rise from the mem- 
brane f. (Some of the cells entering into the formation of the chorion, 
which had not fully coalesced, were still visible ; but they have not been 
represented in the figure.) The large twin cells (bs), constituting the 
germ, were remarkably pellucid, though on the point of being liberated 
by the liquefaction of the surrounding cells, and of a previously invest- 
ing membrane. This ovum was taken from the same Rabbit as that in 
fig. 207. 100 diam. 
205. An ovum of fifty-two hours, found in the uterus with the ova in figs. 202 
and 203. The chorion (cho.) had attained the diameter of , but 
the drawing was not taken until six days after death, during which 
time it is possible that fluid had been imbibed ; though this is not usually 
the case. The membrane f had an ellipsoidal form. The large twin 
cells (bs) had been liberated by the liquefaction of a previously circum- 
scribing membrane, but the remains of cells were visible around them, 
and also two cells nearly perfect and of considerable size. 100 diam. 
PLATE XXVI. 
All the Figures are from the Rabbit (Lepus Cuniculus, Linn.). 
206. An ovum of 23^ hours, from the middle of the Fallopian tube, and mea- 
suring in diameter about fs"' It was taken from the same Rabbit as 
the ova figs. 208 and 209. The pellucid centre in each twin cell had 
increased considerably in size (par. 348.). The objects previously sur- 
rounding the twin cells having liquefied, the latter (bs) alone occupied 
the centre of the transparent fluid contained within the membrane /' 
