520 MR. F. E. BEDDARD ON THE [ Apr. 27, 
ovarian vein, on the other hand, entered the left renal. In one 
of the two examples which I dissected, and of which I took more 
elaborate notes, a small vessel running along the ureter also entered 
the left renal. In this specimen the left suprarenal vein before 
entering the left renal received a branch from the parietes ante- 
riorly, and there were two large lumbar parietal veins entering 
the postcava before its posterior bifurcation and asymmetrically ; 
the left vein entered the postcava higher up than the right. 
Although these vessels ran towards the uterus, they did not, 
as it appeared to me, receive any affluents from any part of the 
generative system. 
In Mus coucha the conditions which obtain are very much lke 
those seen in Votiomys. The two renals are asymmetrical in the 
same way and the ovarian veins have precisely the same connec- 
tions, which, on account of their identity, I need not recapitulate. 
There are two other veins which correspond in their distfibution 
to the lumbar parietal veins of Votiomys, but which are differently 
connected with the postcaval. On the left side of the body the 
vein in question enters the left renal to the inside of the point of 
entrance of the left ovarian vein, but quite independently of it. 
On the right side of the body this parietal vein has quite a different 
connection, for it joins the right ovarian vein before the latter 
debouches into the postcaval vein opposite to the entrance of the 
left renal. 
Otomys irroratus agrees with Notiomys cervinus in the dis- 
position of the postcaval and its branches. The two renals are 
asymmetrical, the left, as usual, being below the right. Into the 
left renal flows a vein which is composed of two chief affluents, a 
vein from the ovary itself and a longer vein from the uterus. On 
the right side the same two veins are present, and form a common 
trunk which flows into the postcava just opposite to the entrance 
of the left renal. The two suprarenal veins enter the postcaval 
independently of the renals. The left suprarenal has a curious 
course; it actually pierces the liver on its way to join the post- 
caval. Below the ovarian veins a large lumbar parietal vein on 
each side joins the postcaval. These are nearly if not quite 
symmetrical. 
In Arvicanthis pumilus there are no great differences. The 
renals are not symmetrical ; the left is joined by the ovarian vein, 
while the right ovarian vein enters the postcaval a little way 
below the entrance of the left renal. 
The few Rodents upon which I am able to report in the present 
communication very clearly show that this group is by no means 
so uniform as the American Edentates or Marsupials. It is 
furthermore plain that the Hystricomorpha present uniform 
characters in the posteaval vein and its branches. There are no 
differences of importance among the six genera belonging to this 
group which I have examined. 
The Myomorpha, on the other hand, are by no means so 
+ 
uniform. Hydromys is like the Hystricomorpha ; Mus, Votiomys, 
