28 



ARON. 



The values vary somewhat, but there is no indication that the organs 

 of the animals kept on a lower diet lost in -weight. On the contrary, the 

 percentage weight of the organs of number XI is slightly higher than 

 that of the control dogs of the same age, but of more or less normal live 

 weight. 



In experiment I the proportion of total solids in the organs was also 

 determined. As Table 2 shows, there is practically no difference in the 

 amount of dry organs, expressed in percentage of live weight, for the 

 three different dogs. 



There is little to be said about the behavior of the different organs. 

 It appears in general that those of the digestive tract (liver, kidneys, 

 and intestines) have increased somewhat, while the others, such as the 

 spleen, heart, and lungs, have suffered a slight loss. 



The brain deserves special consideration. In experiment I the weights 

 of the brains of the three dogs did not differ in the same way as those 

 of the other organs. Their weights were nearly identical, in spite 

 of the difference in body weight of the animals. The same holds true 

 for experiment III. In experiment II the dog of smaller body weight 

 (VI) had a heavier brain than the normally developed animal (V). 

 However, Table 9 shows that the absolute amount of solids in both brains 

 is nearly the same, being slightly smaller in that of dog VI than in that 



of dog V. 



Live weight and hrmn weight in eight dogs. 



Number of dog. 



Live 

 weight. 



Weight 

 of brain. 



II (C)"- 



III (C) 



IV (N)> 



Grams. 

 1,940 

 1,750 

 2,850 



Grams. 

 60.3 

 50.1 

 59.9 



V(N). 

 VI (C). 



XI (O — 



XII (N)_. 

 VIII (N)- 



5,885 

 2,710 



1,100 

 2, 375 

 8,000 



52.0 

 58.0 



49.0 

 48.0 

 57.0 



" (N) Grew under normal conditions. (C) Kept at a constant weight. 



The figures in the foregoing table show conclusively that the brain 

 has nearly the same weight in a dog kept at a constant weight as in a 

 normally developed animal. 



The weight of the brain in relation to the body weight in a younger 

 animal is higher than in an older one, and the brain does not grow in 

 the same proportion as do the other organs. This is well illustrated 



