264 
Proceedings of Royal Society of Edinburgh. [sess. 
On the Placentation of the Halicore Dugong. 
By Professor Sir William Turner. 
(Read July 1, 1889.) 
{Abstract.) 
The only observations hitherto recorded on the placentation of 
the Dugong are by Paul Harting, of Utrecht, in 1878, who ex- 
amined the foetal membranes of a foetus 27*8 cent. long. He stated 
that the placenta was diffused and non-deciduate.* 
The gravid uterus described in this communication was pre- 
sented to the author by C. W. de Yis, Esq., M.A., curator of the 
Queensland Museum, Brisbane, through Professor Anderson Stuart 
of the University of Sydney. 
The uterus was bicornuate, and contained a single foetus, 5 feet 4 
inches long. The foetus and its membranes occupied the left cornu, 
and there was no extension of the membranes into the right cornu. 
The chorion was an elongated sac, upwards of 5 feet long from 
pole to pole. 
The placenta formed a zone a little on one side of the equator 
of the chorion. The zone was 11 J inches broad in its widest 
part and 6 inches at its narrowest. The rest of the chorion was 
smooth and free from villi. The villi were closely crowded together 
in the foetal placenta ; as a rule they were short, though longer 
villi were interspersed amongst them ; they were cylindriform and 
filamentous in shape, and branched seldom except near their free 
ends. 
The allantois was very extensive, and reached to the opposite 
poles of the chorion. Connected to the outer wall of its sac, 
formed by the endochorion, were a number of plate-like allantoic 
bodies. 
The amnion was very capacious, and was completely surrounded 
by the allantois, except for a limited area in the region of the 
placenta. Ho amniotic corpuscles projected from its inner surface. 
The uterine mucous membrane had a zone which formed the 
maternal placenta, and which corresponded in form, size, and 
* See abstract of his paper in the Journal of Anatomy; vol. xiii. p. 116. 
