OVARIAN FOLLICLES IN FERRETS AND FERRET-POLECAT HYBRIDS. 359 
ovum was in the first polar body stage, but the polar body does not lie in the plane of the section. In the 
plane of section the membrana interna is separated from the follicular epithelium for some distance on each 
side of the cumulus, and the secondary liquor folliculi, extending more rapidly in a plane at right angles to 
the plane of the section, has reached the superficial part of the follicle, and in its progress, along a relatively 
narrow pathway, it has invaginated the membrana interna towards the centre of the follicle. (Specimen 
F.G.A. 2/15. R.F1. 41$ hours.) E. 
Fig. 26. Section through a recently ruptured ovarian follicle of a ferret 41$ hours after insemination, 
x 30. The ovum from the follicle is in the middle third of the oviduct in the pronuclear stage. A portion 
of the membrana interna is still adherent to the follicular epithelium on the lower part of the right-hand 
wall of the follicle, but the membrana interna has disappeared from the greater part of the area, and the 
cavity of the follicle is filled with- liquor folliculi tertia, which plugs the orifice, in the follicle wall. The 
liquor folliculi tertia consists of fluid interspersed with strands of fibrils which are connected with the follicle 
cells. (Specimen F.D. G/16. L.Per. 41$ hours.) I.H. O.G. 
Fig. 26a. A portion of the lower and left part of the follicle shown in fig. 26. x 260. Showing the 
relation of the stroma of the tertiary liquor to the follicle cells. The plane of section is 20/x from that shown 
in fig. 26. 
Fig. 26b. A portion of the floor of the follicle shown in fig. 26, in the same plane as the section shown in 
fig. 26b. x 260. Showing the characters of the follicular cells and the relation of the cells to the tertiary 
liquor. 
Plate V. 
Fig. 27. Section through a ruptured ovarian follicle of a ferret 41 hours after insemination. x 30. 
The ovum from the follicle is in the middle third of the oviduct in the stage of fusing pronuclei. As 
contrasted with the follicle shown in fig. 26, the orifice of rupture is smaller, the wall is more folded, and the 
blood-vessels round the external periphery of the follicular epithelium are more numerous. (Specimen 
F.D. 1/16. R.Per. 41 hours.) I.H. O.G. 
Fig. 27a., Section through the orifice of a follicle in the same stage as that shown in fig. 27. x 260. 
Showing (a) the relation of the plug to the left-hand margin of the orifice, ( b ) white blood corpuscles in the 
liquor folliculi, (c) the relation of the strands of the tertiary liquor and the relation of the blood-vessels 
to the follicular epithelium. (Specimen F.D. 1/16. R.Per. 41 hours.) I.H. O.G. 
Fig. 27b. Section through a part of the floor of the same follicle as that represented in fig. 27a. x 260.- 
Showing white blood corpuscles and follicle cells in the tertiary liquor. 
Fig. 27c. Section through a portion of a follicle in the same stage as that shown in fig. 27, and from 
the same ovary, x 260. Showing the relation of the follicle cells in the tertiary liquor to the strands 
of the stroma. 
Fig. 28. Section through two adjacent ruptured ovarian follicles of a ferret 44§ hours after insemination, 
x 30. Showing different stages of contraction of ruptured follicles. In the right-hand follicle the orifice 
'is widely open, and few remnants of the liquor folliculi are left in the cavity. In the case of the left-hand 
follicle the orifice is firmly plugged and a considerable amount of liquor is present in the superficial part of the 
follicle. (Specimen F.D. K/16. L.M.F. 44-§ hours.) I.H. O.G. 
Fig. 29. Section through a ruptured ovarian follicle of a ferret 70 hours after insemination, x 30. The 
orifice of the follicle is contracted and plugged, but redistension of the cavity has not commenced. The 
blood-vessels around the periphery of the follicular epithelium are relatively few, but there are numerous 
small blood-vessels amidst the cells of the follicular epithelium. (F.D.A. 22/15. L.Z.) I.H. Mallory. 
Fig. 30. Section through a ruptured ovarian follicle of a ferret 64$ hours after insemination. x 30. 
The orifice of the follicle is contracted and firmly plugged. There are remnants of the tertiary liquor 
folliculi and its stroma in the remains of the cavity of the follicle. There are few blood-vessels around the 
periphery of the follicular epithelium and amidst the follicle cells, and redistension of the follicle has not 
commenced. The folding of the follicular epithelium layer and the adjacent connective-tissue stroma of the 
wall of the follicle is very marked. The ova from the specimen ovary from which the section is taken are 
in the middle third of the oviduct, one in the 2-cell and others in the 4-cell stage. (Specimen F.G.A. 
5/15. L.Z. 64$ hours.) I.H. 
TRANS. ROY. SOC. EDIN., VOL. LII, PART II (NO. 13) 
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