128 Journal of the Asiatic Society of Bengal. [N.S., XVII, 
> . 
of the 11 successful experiments, the authors expressly state 
tnat ‘‘no glomeruli were injected” and that the tubule 
probable that this was due to influx from the intertubular 
capillary plexus rather than to some twigs of the renal 
arteries having remained uncauterized, ' since we have seen 
that Nusshaum’s and Beddard’s statement that ‘“‘it is 
impossible to inject the glomeruli from the renal-portal vein ”’ 
is untrue, provided that the pressure in the vein be sufficient. 
These experiments on the whole therefore (and possibly 
those of Nussbaum (30) and Halsey (21) who similarly obtained 
urine from frogs with cut-out renal arteries, after injecting 
diuretics directly into the blood—which, as Cushny points out, 
alone secrete the urine, the function of the glomeruli being 
altogether different (see Part IV). ; 
Bainbridge, Menzies and Collins (5) maintain, however, 
despite the conclusive evidence to the contrary provided by the 
control dye injections of Bainbridge and Beddard, that urine 
formed by perfusion through the renal afferent veins, the 
arteries being ligatured, is always produced by the fluid perfused 
reaching the glomeruli, because whenever, in their experiments, 
urine was secreted as the result of very high pressure in the 
perfusion fluid, subsequent injection of Berlin blue always result- 
ed in the dye being found in the glomeruli, whereas when, wit 
low pressure, urine was not secreted, few or no glomeruli were 
found to contain the dye. This, I may remark without dis- 
respect to these authors, is an admirable practical illustration 


! Each operation however was done from the ventral side, when it is 
not so easy to be certain that every arterial twig has been severed as it 18 
in a dorsal operation. 
