536 
DR. MARTIN BARRY’S RESEARCHES IN EMBRYOLOGY. 
Disappearance of the Orifice in the thick transparent Membrane (“ zona pellucida") 
after Fecundation. 
344. This orifice I have in no instance seen after the discharge of the ovum from 
the ovaiyf-. It was distinct in an ovarian ovum of six hours (figs. 173 to 175.), cer- 
tainly fecundated ; in another ovarian ovum from the same Rabbit, which had also 
undergone fecundation, no trace of it could be seen. It is very possible, however, 
that in the latter instance, as well as in others where I have failed to find it, the 
opening was situated on the under surface of the ovum. Very probably the fissure, 
for such it generally seems, closes before the ovum leaves the ovary. 
Changes in the Tunica granulosa immediately after Fecundation. 
345. The cells of this structure undergo a remarkable alteration in position, size, 
form, and internal condition. Being first loosened and made less adherent to one 
another, they become club-shaped, greatly elongated (some of those in Plate XXVIII. 
fig. 245. measured in length), and connected with the thick transparent mem- 
brane f by their pointed extremities alone (Plate XXIII. figs. 173. 181., Plate XXV. 
fig. 195.). They present in their interior, at the large extremity, a pellucid space (Plate 
XXVIII. fig. 245. «.), apparently corresponding to the enlarged nucleolus of other 
cells This space is surrounded by dark globules. Subsequently there is seen 
instead of this pellucid space, a cell-like object which contains a colourless and 
transparent fluid (fig. 245. (3.), but does not exhibit any proper nucleus or “ cyto- 
blast,” and the surrounding globules become scattered. At a later period (fig. 245. y.), 
these cells of the tunica granulosa are found filled with other cells §. 
CHANGES IN THE OVUM AFTER ITS DISCHARGE FROM THE OVARY.— ADDITION OF 
THE CHORION. 
(These changes are represented in Plates XXIV., XXV., XXVI., and XXVII. The 
ova there seen were of periods varying from 1 1 to 76^ hours, and they measured in 
diameter from to i'"||.) 
The Germ or Foundation of the New Being ; its Place of Origin and Form; the Ger- 
minal Vesicle not a Nucleus, but a Parent-cell. — Reproduction of succeeding Cells . 
346. In a former page (par. 327.) it was shown that the free portion of the germinal 
f See, however, “ Second Series” l. c., par. 178. fig. 109, and par. 190. 
I Compare with “First Series” l. c., fig. 44. <p, and fig. 73, “ Second Series” l. c., figs. 102. g, g, 88. 89. 
93.96. 97. b., 105±. 114. 115. 116. bb., 118. 120. 121 A. B. C. D„ 122. bb l . 129. 132. 135. 138. 139. 148. 
149. 150. 152. 153. 154. See also a great number of figures in the present paper. 
§ The second and third of these conditions, however, so far as my observations have extended, are not gene- 
rally met with until the ovum has been discharged from the ovary. 
|| Figs. 198 and 201. in Plate XXV., represent ova of only 5^ hours from the ovary. Their unusually 
advanced state rendered it proper to place them among ova from the Fallopian tube. 
