PROFESSOR W. TURNER ON THE PLACENTATION OF THE APES. 
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through the placenta to reach the compact layer of the decidua. 
The blue colour is intended to indicate the blue injection in the 
blood vessels of the chorionic villi. (Page 5-32.) 
Fig. 6. A portion of the chorion, with the stems of two of the villi arising from it 
dissected out of the placenta of Macacus cynomolgus. The uniformity in 
size of the stems throughout their length, and the numerous branches to 
which they give origin are represented. The blue colour is intended to 
show the blood vessels magnified. (Page 532.) 
Fig. 7. Vertical section through the placental chorion and a small part of the stem of 
a villus from the same placenta. X 20. 
am. The layer of amnion. 
ch. The chorion containing divided blood vessels 
sch. The layer of sub-chorionic cells prolonged on the stem of the villus. 
(Page 533.) 
Fig. 8. Vertical section through a portion of the chorion of the same placenta. X 350. 
am. Amnion. 
ch. Chorion. 
ich. Intra-chorionic cells. 
sch. Sub-chorionic cells. (Page 532.) 
Fig. 9. A portion of one of the septa between the areoke in the spongy layer of the 
decidua serotina of Macacus cynomolgus. X 350. 
e. The epithelial cells with their large nuclei. At se the epithelium has 
been shed and the subjacent fusiform corpuscles and lymphoid cells 
of the sub-epithelial tissue are exposed. The darkly-shaded tube is 
a blood capillary situated in the sub -epithelial tissue. 
Fig. 10. Vertical section through the uterine wall and decidua serotina of the same 
animal. X 65. 
m. Muscular coat containing divided blood vessels. 
s. Decidua serotina containing areolse. 
aa. Hillock-like elevations of the serotina projecting into the interior of 
the placenta. 
v. A villus with its contaiued blood vessel, injected blue, penetrating 
into the interior of a large hillock of decidua. (Page 534.) 
Fig. 11. A section through the compact layer of the decidua serotina and a view of 
one of the hillock-like prolongations of the same placenta. X 350. 
s. Compact layer of decidua serotina. 
a. A hillock-like prolongation. The cellular structure of both is shown, 
and some isolated cells are represented detached from the serotina. 
The pale blue colour, v, shows the injection in the vessels of the 
stem of a villus embedded in and surrounded by the decidual cells 
of the hillock, and from it some idea may be formed of the extent 
4 c 
MDCCCLXXVIII. 
