555 



Experiment 24 (Sept. 14). 



The same perfusion liquid as in experiment 23. 



0,1 cc. urine of right kidney: (),i'.i cc. Iodine solution; reduction 0,0775'V(). 



0,1 cc. urine of left kidney : 0,44 cc. Iodine solution ; reduction 0,08"/o. 



Betained by right kidney: 08-0,0775 = 0,0025% 



Retained by left kidney : 0,08—0,08 = 0. 



We see tlms that willi galaiMose as well as with glucose, tiie 

 qiianlity of NaHOOj in the petfiisioii liquid is of greal importance 

 for the permeability of the glomerulus epithelium. A solution con- 

 taining a small quantity of NaHCOj causes galactose to pass in toto; 

 if the perfusion liquid contains a physiological quaiitity of NaHCOg 

 (0,285 7o) then on an average 0.025 70 galactose is retained. We say 

 on an average, as frogs present individual differences. 



Here follows a table which gives a summary of a series of other 

 experiments with galactose in which however the quantity of 

 NaHCOj was, accidentally, 0.2 7„ instead of 0.285 7„. As had also 

 formerly been found with glucose such a modification was of very 

 little importance. 



Retention capability of kidney for galactose. 



When we make a study of this table it becomes clear; 



1. that there is a difference in the power for retaining galactose 

 in the various frogs A,B, C, D, E, and F. 



2. that the individual differences range between and 0,0337o- 



3. that the power of retention is more or less the same for the 

 right and the left kidney of the same frog. 



Hei'e again as in the fanner experiments it is clear that galactose 



