26 RICHARD ASSHETON AND THOMAS G. STEVENS. 
of the facts as given above, but seeing how improbable it is 
that more suitable material will be obtainable in the immediate 
future we must risk the attempt. 
As a result of our investigation, certain questions at once 
present themselves. Do our investigations confirm Turner’s 
conclusion that the elephant’s placenta is deciduous ? What 
is the origin of the syncytial layer; does it belong to the 
foetal or maternal tissue? What is the origin of the walls of 
the maternal channels; are they foetal or maternal? How does 
the placenta compare as regards its minute structures with 
other known placentas ? 
Turner defined a deciduate placenta as one in which there is 
a “shedding of the vascular part of the maternal placenta 
during parturition.” He came to the conclusion that the 
elephant’s placenta is without doubt deciduate. 
The placenta, as will be gathered from our description above, 
is at first sight more like the type of placenta found in 
those orders called deciduous than that of the true ungulates, 
lemur, etc., and known as non-deciduous. There can be no 
doubt about the shedding of at any rate part of the maternal 
vascular system. But for all that it is impossible to speak 
with certainty, except as regards the blood, from so scanty a 
supply of material; and it is not absolutely certain that any 
maternal tissue except the blood, which obviously comes 
away in large quantities, is lost during parturition. In the 
after-birth the great mass of tissue is without doubt foetal. 
Of the three regions, A, B, and C, of our description of the 
full-term specimen, region A is wholly and region C mostly 
foetal. That this is true of region A needs no explanation. 
As regards region C the matter is less obvious. We find, 
however, some tissue which we must regard as a remnant of 
the homogeneous material described in Section II. on the 
Owen placenta. This contains nuclei, which are probably of 
the thick inner layer of that material and therefore tropho- 
blastic ; and very occasionally we think we can detect one of 
the rounded cells with small nucleus which we have ascribed 
to maternal tissue. 
