576 
PROF. W. TURNER ON THE PLACENTATION OE THE LEMURS. 
surface of the mucosa surrounding the os uteri, beneath the smooth patch of membrane 
situated in the fundus of the gravid horn and beneath the smooth mucosa lining the 
non-gravid horn : in each of these localities the glands opened on the smooth free 
surface. Quantities of epithelium-cells were contained in the gland-tubes. The cells 
did not, as a rule, form a continuous lining, but were broken up into separate masses. 
As a rule, also, the epithelium lining the gland-tube near its mouth was not in situ , and 
that which had formed the covering of the smooth areas was shed. The long interval 
between the death of the animals and the time of examination, together perhaps 
with the action of the salt, will, I think, sufficiently account for the loosening of the 
epithelium-cells in these localities. The number of gland-tubes in the deeper layer of 
the mucosa was greater than near the surface, so that each gland stem or duct, as it 
approached the surface, must have received the secretion of several of the deeper tubes. 
The chorion occupied the cavity of the corpus uteri and gravid horn, and gave off 
from the depending part next the os uteri (the so-called cephalic pole of M. A. Milne- 
Edwards) a short prolongation, having the appearance of a diverticulum, which passed 
into and occupied the cavity of the non-gravid horn. This diverticulum was best 
marked in B, in which it measured inch in length ; so that the chorion might be 
described as extending from the tip of one cornu, through the corpus uteri to the tip 
of the opposite horn. The extension of the chorion into the non-gravid horn had not 
been recognized by M. A. Milne-Edwards in his specimens ; so that whilst he quite 
correctly regarded that enveloping the caudal end of the foetus as one pole, he supposed 
the portion of this membrane which was next the os uteri to be the opposite pole. But 
the true poles of the chorion are the ends situated in the horns of the uterus, whilst 
the part covering the head of the foetus is not a true pole, but the most depending part 
of the membrane next the os uteri. 
The surface of the larger proportion of the chorion was covered by villous ridges, 
similar to those described in Propithecus, and the parts of the chorion in apposition with 
the smooth surfaces of the mucosa were bare of villi. Thus a bare surface of some size 
was at the caudal pole of the chorion in the fundus uteri ; another bare surface was on 
the opposite pole in the non-gravid horn, and a still larger bare surface was on that 
part of the chorion which, enveloping the head of the foetus, lay opposite the os uteri. 
The parts of the chorion which were in apposition with the irregularly elongated 
smooth areas of the mucosa lying amidst the crypt-covered surface were also non- 
villous. The chorion had the usual structure of that membrane, and its epithelial 
covering was distinct. I did not succeed in obtaining an injection of the umbilical 
vessels ; but there can be no doubt that the villi were highly vascular ; and from what I 
have seen in other animals possessing a diffused arrangement of the villi over the 
chorion {e. g. Pig, Mare, Orca, Narwhal, Dromedary), it is also very probable that a 
network of capillaries was distributed beneath the intervillous parts of the membrane. 
The chorion of C was then cut through by a longitudinal incision, and the sac of the 
allantois was opened into. It was 4 inches long, and extended from the caudal pole 
