NOTES ON STRUCTURE, ETC., OF ELEPHANTS PLACENTA, 35 
foetal placenta. Some of the ends of the villi in this region are covered by a 
plasmodial remnant (p/.). The region lettered D indicates the probable 
relation of the uterine surface to the after-birth. The longest villi penetrate 
into this maternal tissue (V”’). 
Fic. 1 b.—A diagram of a similar region to show the probable relation of 
the blood channels to the maternal vascular system. A is an arterial! vessel 
carrying blood from the uterine vessels U V A to region B, where it 
circulates in the channels round the villi and collects into large efferent, 
vessels, which open into irregular spaces in region C, whence it is supposed 
the blood passes into maternal veins, U V V. 
Fic. 2.—A camera drawing of a portion of asection taken vertically through 
the placenta showing the features characteristic of region B. The wide 
maternal channels (m. ch.) are filled with corpuscles. The mesoblast tissue 
of the foetal villi and their branches are coloured darkly. Many feetal 
capillaries are seen cut across transversely (f c.). Between the foetal meso-' 
blast and the blood-channels containing maternal blood an irregular layer of 
syncytium (cy.) is seen which can almost without doubt be called trophoblast. 
x 340. 
Fic. 3.—A camera drawing of a piece of region C, from a section taken 
vertically through the placenta. The large foetal blood-vessels (f 8.) in the 
large trunks of the villi and the small terminations are clothed by a columnar 
epithelium (¢7.), probably the trophoblast. These epithelia have shrunk away 
in many places and adhere to a coagulum, which is partly blood-clot and 
partly remnants of a trophoblastic plasmodium and cell detritus. x 75. 
Fic. 4.—A section of a foliaceous termination of a fcetal villus in region B 
cut parallel to its broad surface, showing the network of fine capillaries. 
x cire. 200. 
PLATE 2. 
Fic. 5.—A group of leucocytes in a space among the tissues of a feetal 
villus. x cire. 200. 
Fic. 6.—A section taken across a fcetal villus cutting a fcetal vein and 
artery transversely. This shows the large spaces in the mesoblastic tissues 
filled with leucocytes. Adjoining this is a maternal blood-channel of moderate 
size also crowded with leucocytes. x 95. 
Fie, 7.—A camera drawing of a section through the boundary between 
region B and region C. At the point z a communication between the vascular 
channels of region B and the irregular blood-space of region C is shown. 
xX 75. 
Fic. 8.—A piece of a maternal blood-channel from region B to show the 
sinuous baggy nature of these channels and the endothelial character of cells 
found lining the walls (end). x cire. 200. 
