600 
DR. MARTIN BARRY ON THE CORPUSCLES OF THE BLOOD. 
The Chorion formed of Cells derived from Corpuscles of the Blood. 
20. When the ovum is sought for in the Fallopian tube in the manner recommended 
in my “ Second Series” on Embryology (/. c., par. 313.), it is very common to find, in 
the mucus, patches of more or less altered blood-corpuscles. Plate XXIX. fig. 6. 
presents a minute portion of one of these patches, from the Fallopian tube of a Rabbit 
killed twelve hours post coitum. Many of the corpuscles (a), still flat, had undergone 
little change besides being pressed together into six-sided figures. Others ((3) had 
become orange-shaped, highly refracted light, and presented in their interior a bril- 
liant object, which in some instances (y) was seen to be not central, but situated on 
one side. The diameter of the objects (3 was in general rather less than that of the 
unchanged corpuscles a. Whether this difference in diameter was referable to the 
change from a flattened to the more globular form, which would perhaps be sufficient 
to explain it'f~, — -or whether an outer covering (present in a) had disappeared in (3 , — I 
do not know ; but the occasional presence of extremely minute granules or globules 
around such objects (e), leads me to think it very possible that the disappearance in 
question does take place. If the figure be closely examined, and more particularly 
on the left side, transition states will be observed between the unaltered corpuscles 
a, and the cell (for such it may now be termed) (3. The figure presents several cells 
(5) in which a further change had taken place. They had become elliptical. 
21. In Hate XXIX. fig. 7. are seen blood-corpnseles, now cells, from the Fallopian 
tube of a Rabbit killed fourteen hours post coitum. Some of these (&) were in a state 
resembling that of l in fig. 6. Others had enlarged, and presented processes or arms. 
W 7 hen viewed singly and highly magnified, such objects appear yellowish ; an accu- 
mulation of them, seen by the unassisted eye, or with a low magnifying power, is 
blood-red. 
22. I formerly showed^ that during the passage of the ovum through the Fallopian 
tube, there rises from the thick transparent membrane (f) a thinner membrane. The 
latter was traced from stage to stage up to the period when villi form upon it, and 
thus ascertained to be the incipient chorion. 
23. In a later paper § I stated that the thin membrane in question (the incipient 
chorion) is formed of cells, and that these are not cells of the ovarian so-called “disc,” 
but newly-arisen objects, the nature of which more particularly would be made known 
in a future paper. 
24. If now my last memoir be referred to§, it will be found that the cells repre- 
sented in Plate XXVIII. fig. 252 and 253. of that memoir, as forming the incipient 
chorion, have the same appearance as some of those in Plate XXIX. fig. 7 . of the 
t It did not escape the notice of Hewson, that the diameters of the red particles of human blood diminish 
from the particles becoming spherical, l. c., pp. 18, 19. 
X Researches in Embryology, Second Series, l. c., pars. 172. 222. Plate VI. fig. 104. a and /j. 
§ Researches in Embryology, Third Series, l. c., pars. 370 to 373. 
