PROFESSOR W. TURNER ON THE PLACENTATION OF THE APES. 
561 
interest in connexion with an observation made by M. Breschet on the placenta in 
Cynocephalus sphynx. * M. Breschet states that in his specimen the placenta appeared 
to be single, but, influenced apparently by the idea that the placenta was double in 
the Monkeys of the old world, and single only in those of the new world, he thought 
that from the torn condition of the membranes a smaller subordinate lobe had been 
destroyed by the mother. It is probable, however, that in M. Breschet’s specimen, 
as was certainly so in my own, only a single placenta was present. Hence it would 
appear that in the Baboons, as in the Chimpanzee, the placenta consists of only a 
single lobe, so that the opinion which was at one time entertained that the Apes of 
the old world could be distinguished from those of the new by the invariable presence 
of a bi-lobed and not a single-lobed placenta is not borne out by more extended 
inquiry. 
Both in the placenta of Cercocebus and Cynocephalus, as in the previously described 
Macacus cynomolgus, the placenta was divided by farrows into lobelets. The uterine 
surface of the shed placenta of Cynocephalus was covered by a well-defined layer of 
decidua, which was ragged on its uterine surface, owing, doubtless, to the tearing 
through of the thin walls between the loculi, similar to those I have described in 
Macacus. Several utero-placental veins, which had been torn across, lay in grooves 
in the placental decidua, usually in the furrows between the lobelets and opened by 
obliquely directed mouths into the interior of the placenta, the villi within which 
could be seen through the venous orifices. Those villi which were placed next the 
edge of the mouth of the vessel were adherent to its wall, so that a provision existed 
which would admit of a prolongation of the endothelial wall of the vessel on to the 
villus. When the placenta had been steeped in spirit, a quantity of the fluid had 
soaked into its interior, and could by gentle pressure be squeezed out through the 
mouths of the utero-placental veins, which proved that a free communication existed 
between these vessels and the interior of the placenta. The torn veins closely 
resembled those figured by John Hunter on the uterine surface of the shed placenta 
of his Macacus rhesus. 
But in addition to the vessels that I have described as veins, I saw other vessels 
attached to the uterine surface of the placenta of Cynocephalus, which I believe to 
be the utero-placental arteries. They were smaller in size than the veins, but yet 
sufficiently large to enable me to pass a pig’s bristle into the lumen. One in particular 
was traced for about an inch, extending with a slightly wavy course in close contact 
with the uterine surface of the organ. Another could be traced for half an inch covered 
over by a thin pellicle of decidua to open into the placenta about the middle of a 
lobelet. 
The detached lobe of the placenta of the Sooty Mangeby had also its uterine surface 
covered by decidua, and a thick layer of decidua, showing numerous loculi, was left 
on the placental area of the uterus, and in both the torn -across mouths of utero- 
* ‘ Memoires de lTnstitut,’ 1845, p. 452. 
4 C 2 
