1922.] — “ Renal Portal’ System. 187 
The results of the preceding nine experiments (six recorded and three 
menti 2) as explained in tho text, that quantity of urine is, 
0 
depends upon the ‘bre ssure ohaih iis comes from the aorta or the 
post-caval. The reverse current pasinuaeh described in Part IV fur- 
ther — 8 ae ntity of urine also depends, other things equal, upon 
: ns ; : : 
ae fails—the pressure is not s t to for cigar” Hea ie gh acM di 
of fluid through the efferent Bi ni $j; on af x other hand, fluid 
under a very low pressure perfused via the nal vein, and therefore 
traversing no glomeruli, gives an ample supply. od rg and likewise 
volume without flow is equally a as is i y the experi- 
ments of ae Ser. vik C.T.P. On several occasions T nia in “Ale frog the 
experiment of perfusing saline and ta via the aorta at 40 cms. pressure 
and then texting the post-caval, the aorta behind the a and the 
renal afferent veins, but in each case there was so much extravasation 
e 
Sel ca arently 
compensate for lack of flow to a very large ex chant. perhaps altogether 
vide e.g. the experiments of Bainbridge and Beddard (3), and other 
thors). 
APPENDIX H. 
Reversal of the Current of Perfusing Fluid through the Kidney. 
pee imenic! Series 1. tee through the frog’s kidney in the 
e direction to the normal. 
OP 1. [In this experiment I first attempted t 
sample of urine with 0°6% saline (tap een —— 
in the aorta (a rid 2 mats | aocomgp the tubing of 
the cat ae nts the two r.a.v. _— 
clamped. The | soy cut cut and the two 
ra.v. cut behind the. cannulae. The experiment 
| ins 6 70 po | being im iately after insertion. Be- 
1 ween 9°15 and 10°10 less than 0:2 ¢.c. urine 
r.av. Mics J hg — although between 9°20 and 10°10, 
of fluid had perfused through the aorta. | 
Saline + ears At 10- 2 A substituted in the aortic bottle 0°6% 
in aorta _ ne (tap apitriitg each 2000 c.c. containing 
closed. human Put collecting echen from 
10 30-11: 30 and. collected l c.c. urine [1 ¢.c. = DC 
{direct current urine) }. 
[10-30-11-30 ae perfused 695 c.c. (increased flow 
due to increased osmotic pressure) ]. 

A fact also ‘usa oo by the ae of the actual flow 
— te increase of os c pressure in the renal afferent vein (see p. 18 
art I). 
