1922.] * Renal Portal” System. 91 
remain in a living healthy condition (as determined by gas 
‘metabolism results) after perfusion with saline at room 
temperature (therefore much lower in this case than the body 
temperature) for at least eight or nine hours and can retain its 
vitality even when wholly deprived of oxygen for a much longer 
period, afford a sufficient answer to the off-hand criticism that 
the results of perfusion experiments on the kidney must be 
unreliable, owing to the kidney cells being necessarily in a 
condition of “ partial asphyxia’’ and therefore unable to 
function normally. It is moreover remarkable that those who 
advance this criticism, even in connection with experiments 
and injected altogether with 74 ¢.c. of diuretics, -secreted 
about 22-5 c.c. urine: from which data it is certainly unjusti- 
operated on from the dorsal surface, that all dorso-lumbar 
veins and all small muscular and cutaneous arteries arising 
from the aorta were carefully ligatured, that the lymph hearts 
posterior to the kidney were extirpated, that the ureters were 
