The histology of the early placenta of Macacus nemestrinus. 299 
The histology of the early placenta of Macacus nemestrinus. 
By W. L. H. Duckworth, M.D., Sc.D., Jesus College, University 
Lecturer in Physical Anthropology. 
\_Reacl 25 February 1907.] 
Among the numerous specimens presented to the Anatomical 
Department by Dr C. Hose is the uterus of a female Macacus 
nemestrinus monkey from Sarawak, Borneo. The anterior uterine 
wall had been cut into, and when the posterior wall of the uterus 
was exposed, a small hemispherical projection was noticed springing 
from the upper portion. In general appearance, the uterus closety 
resembled the uterus of a female “Lutung” monkey (Semnopithecus 
pruinosus) drawn and described by Selenka in 1901*: and again 
there was a distinct resemblance to a similar specimen (but of 
Semnopithecus nasicus) also figured by Selenka in 1900f. 
The present example appeared rather smaller than those 
represented by Selenka, and in equatorial diameter measured 
2“2 mm. only. 
This projecting mass with a block of the subjacent uterine 
tissue was stained in bulk (in carmine) and cut serially into 
520 sections, some of which were afterwards counterstained with 
eosin. 
Figs 1 and 2 represent sections 117 and 295 respectively, 
and shew that the uterus was undoubtedly pregnant but that a 
part only of the blastocyst remains, viz. that portion which has 
contracted an attachment to the uterine wall. The embryo itself 
has fallen out. 
The extreme rarity of specimens illustrating the events 
occurring in the earliest stages of placental development in the 
apes and man, justifies a careful study of the specimen in spite 
of the imperfection alluded to ; and the following account contains 
a resum d of the observations which have been made. 
The orientation of the specimen will perhaps be understood 
better when the sections represented in Figs. 1 and 2 are com- 
pared with Fig. 3 (q. v.). The latter represents the specimen in 
relation to the general uterine surroundings, viz. the wall of the 
uterus and the uterine cavity. The parts no longer present have 
been added in a schematic manner, but it is believed that the 
representation is fairly correct. 
* Selenka: “ Plaeentai'aulage des Lutung,” Munclien. Sitz. der math.-phys. cl. 
der Kyi. bayr. Akad. der Wissensch. 1901, Heft i. Tat'el i. Fig. 1. 
+ Selenka : Studien iiber die EntwicJcelunysgeschichte der Thiere, 8tes Heft, 1900, 
Fig. 25. 
20—2 
