1922.] ** Renal Portal’? System. 113 
Toad B and possibly Toad C might have emulated Toad JJ 
in surviving long enough to allow of the regeneration of the two 
renal afferent veins had they not been chlornformed. Toads D 
E, F and H apparently died from the effects of the excess of 
venous blood supply to the liver (liver unhealthy and contain- 
ing many cysts full of granular matter, swollen gall bladder 
and coelomic effusion) and the deficient arterial blood supply to 
the legs (discoloration and sores on skin of legs due to gan- 
grene), and es in some cases ineffective sterilization of the 
wound (Toad G ?). I have already provided evidence to show 
that the ligature of the two renal afferent veins--the elimina. 
tion of the “ renal Lies ” system—was not per se the cause of 
death or even dise n these toads; the kidneys can gine 
quite efficiently hee “deprived of their venous blo sup- 
On the Hh norease in Size of the Kidneys in Toads ie tei ed 
nui Afferent Veins. The Ligature of one Renal 
erent Vein in Living Toads. 
It may be argued that the enlargement of the kidneys in 
toads with ligatured renal afferent veins is an indication that 
(supposed aera venous te cut off, but, as we have seen, 
the renal arteries do not become enlarged. Moreover, that this 
kidney hypertrophy is of no significance in connection with the 
problem of the “renal portal ” ae is clearly shown by the 
fact that in the abnormal specimen of Rana temporaria, referred 
to above as having been ike of a ‘renal portal”? system 
from birth (the frog OD), the kidneys were slightly below the 
average in size (when compared with the kidneys of six normal 
R. temporaria ). In this connection it is further interesting to 
note that when one renal afferent vein is ligatured in a living 
toad, one kidney therefore being non-portal and the other “ por- 
tal,”’ the non- Laat kidney does not increase in size compared 
with the “ portal” kidney, though both may perhaps enlarge 
equally to a ary small extent. In 1915, Thi ligatured the right 
renal afferent vein in four toads. One died after three weeks 
and three days, one after seven ag and six days, and the other 
two I killed after seven weeks, six days (perfectly healthy, in- 
side and out) and eleven weeks, ais days (bealthy save for a few 
cysts in the liver) respectively. In the first toad the two kidneys 
were exactly equal in weight (each=0°60 gm.) ; in the second, 
the left “ portal” kidney weighed 0 352 gm. and the right non- 
portal 0°315 gm.; in the third, the left ‘‘ portal” kidney 
