516 _ MR. F, E, BEDDARD ON THE [Apr. 27, 
several branches of the postcava in that animal are as in the Hys- 
triciform Rodents, of which I give a certain number of details 
presently. In two out of the three venous systems figured by 
Hochstetter the left spermatic vein entered the left renal vein, 
while the right spermatic vein entered the postcaval a good way 
below the entrance into it of the two renals. A very remarkable 
state of affairs was shown in a third example which I have not 
been able to parallel in any Rodent dissected by myself. In this 
animal the left spermatic artery entered the left parietal lumbar 
vein. 
Of Hystrix cristata 1 have examined the postcaval vein and its 
branches in three examples, in all of which the conditions were 
much the same but not precisely identical. All the renal veins 
showed the usual asymmetry, which need not be further particu- 
larised. In all, the left ovarian vein entered the left renal vein ; 
in two of the individuals the right ovarian vein entered the post- 
caval a good way below the entrance of the left renal; in the 
remaining specimen the point of entrance was higher up on a level 
with the entrance of the left renal, as in the Myomorpha generally. 
In one specimen (I have no notes upon the other two as concerns 
this vein) 1 observed the right lumbar parietal vein to enter the 
corresponding iliac vein and not the main trunk of the postcaval. 
In another specimen (again I have no notes upon the matter in 
the remaining two) the caudal vein was asymmetrical and entered 
the left iliac. 
Chinchilla lanigera is quite like Hystrix cristata; in both of 
two specimens the renals were asymmetrical and the left genital 
vein entered the left renal, while the right genital vein entered 
the postcava some way down. An example of Dasyprocta cristata 
showed the same features. A specimen of the Capybara, Hydro- 
cherus capybara, was identical, save for the fact that the renal 
veins were fairly symmetrical. The left suprarenal vein, it should 
be mentioned, opened directly into the postcaval vein above the 
renals. In a second specimen of this Rodent the renal veins 
were also symmetrical. A specimen of Aulacodus swindernianus 
showed also symmetrical renal veins ; the ovarian veins were as in 
the last three genera. Of the Viscacha, Lagostomus trichodactylus, 
I have dissected the postcava in two specimens. In one the 
renal veins were about symmetrical; in the other the right was a 
little in advance of the left. In both specimens the ovarian vein 
of the left side opened into the corresponding renal, and of the 
other side into the posteava opposite to the left renal. 
The posteaval and its branches in Hydromys chrysogaster (text- 
fig. 138 B) are as follows:—The postcaval itself occupies the usual 
position to the right of the aorta. The renals are asymmetrical, 
the left vein opening below the right in position. The left 
suprarenal vein receives, after leaving the suprarenal body, three 
parietal veins, two anteriorly and one posteriorly. The left 
ovarian vein enters the left renal, and the right ovarian vein 
enters the main trunk of the postcaval not a very great way 
