ALBINO RAT BRAIN IN MULLER S FLUID 



419 



TABLE 6 



Part A. Water relations at the seventy-five day weighmg of fi,Jty-nine whole brains 



{sec table 4) 



Average fresh brain weight 



Percentage of water (from Donaldson, '16) 



Calculated amount of water represented in fresh 



brain 



Final brain weight 



Final amount of water 



Percentage of water — observed 



Increase in weight due to water, gms 



Increase in weight due to salts, gms 



Percentage of salts in total increase in weight 



Percentage of salts in the total water in brain 



OVER 120 

 DATS 



1.826 



78.1% 



1.426 

 2.407 

 1.932 



80.2% 

 0.506 

 0.075 



13.0% 

 3.9% 



Part B. Water relations at the thirty-day weighing of parts of three brains 



OLFAC- 

 TORY 

 BULBS 



0.058 



82.3% 



0.048 

 0.078 

 0.067 

 85.6% 

 0.019 

 0.001* 



4.9% 



1.5% 



Average fresh brain weight 



Percentage of water (from Donaldson, '16) 

 Calculated amount of water represented in 



fresh weight 



Final weight 



Final amount of water 



Percentage of water — observed 



Increase in weight due to water, gms 



Increase in weight due to salts, gms 



Percentage of salts in total increase in weight 



(for total brain 14.8%) 



Percentage of salts in total water in the part 



(for total brain 4.3%) 



fluid, this seems a striking fact, though where the initial per- 

 centage of water is so high, it is evident that it takes a relatively 

 large difference in the absolute water content to markedly 

 affect the percentage value. 



In the three brains divided into their parts the salts are de- 

 posited in the following percentages after thirty days: 



