Proceedings of the Royal Society. 263 
The third new fact which the author adduces is the peculiar 
structure of the funis and placenta of the seal. In this animal 
the vessels forming the funis are not twisted; their whole length 
is 9inches. Three from the placenta, they give off anastomosing 
branches, connected. with it by three membranous folds, between 
which the blood vessels are conveyed to the placenta. This struc- 
ture gives uncommon facility to the placental circulation, and 
makes it worth inquiry whether the same peculiarities exist in 
other marine animals. Several illustrative drawings accompany 
this paper. 
On the same evening a Paper was communicated, entitled 
Further Particulars of a Case of Pneumato-Thorax. By J. Davy, 
M.D. F.R.S. 
About a month after the operation described in Dr. Davy’s 
former paper, when the patient appeared to be doing well, symp- 
toms of hydro-thorax came on, and fluid again collected in the 
left side of the chest;—a second operation therefore was per- 
formed, and 14 ounces of fluid discharged through a perforation 
in the fifth rib. During the six following weeks not less than 20 
pints of fluid ran off through the opening—at first it was transpa- 
rent, but became gradually more and more purulent, and was © 
mixed with air composed of oxygen, azote, and carbonic acid, in 
various proportions. The patient’s health improved at first pro- 
gressively, but in about 6 weeks after the operation he became 
worse, and expired suddenly. On examination after death about 
6 oz. of pus were found in the left pleura, The right pleura was 
healthy, but tubercles and vomice were found in the right lung. 
The left lung was much condensed, and communicated by two 
small openings with the pleura. Dr. Davy referred the origin of 
the disease in this case to a communication between the aspera 
arteria and cavity of the pleura, established by the rupture of a 
superficial bronchial tube and the membrane covering it; he con- 
cluded the paper with some remarks upon the fluctuation and com- 
position of the air from the chest, which he attributed not to the 
varying quantity of atmospheric air admitted through the per- 
