WEIGHTS OF ORGANS IN UNDERFED YOUNG RATS 



137 



two weeks and from ten to thirty-five weeks the heart has ap- 

 parently retained almost exactl}- its initial relative weight. The 

 absolute weight therefore apparently remains unchanged (the 

 differences in the table being due to different initial body-weights) . 

 During inanition in adult rats (Jackson '15 a, '15 c) the heart 

 likewise maintains its relative weight, losing in absolute weight 

 nearly in proportion to the entire body (slightly more in chronic 

 than in acute inanition). 



TABLE 14 

 The thymus; average absolute weight, average percentage weight and range indicated 



TABLE 15 



The heart; average absolute weight; average percentage of net body-iveight and range 



indicated 



DESCRIPTION OF RATS 



Normal at 3 weeks (Jackson '13; 



Controls at 3 weeks 



Body-weight constant 3 weeks (age oi 3 to 6 weeks) 

 Body-weight constant 5 weeks (age of 3 to 8 weeks) 

 Bodj'-weight constant 7 weeks (age of 3 to 10 weeks; 



Normal at 6 weeks (Jackson '13) 



Controls at 6 weeks 



Body-weight constant 26 weeks (age of 6 to 32 weeks) 



Normal at 10 weeks (Jackson '13) 



Controls at 10 weeks* 



Bod> -weight constant 25 weeks (age of 10 to 35 weeks) 

 Controls at 32 and 35 weeks 



ABSOLUTE WEIGHT 

 (and range): GRAMS 



0,135 (0.082 

 0.170 (0.13O 

 0.15) (0.123 

 0.129 (0.128 

 0.166 (0.124 

 0.277 (0.183 

 0.237 



0.271 (0.255 

 0.375 



0.562 (0.489- 

 0.389 (0.348 

 0.873 (0.688- 



0.250) 

 •0.245) 

 •0.187) 

 •0.130) 

 0.213) 

 •0.535) 



-0 288) 



•0.687) 

 -0.450) 

 •1.29) 



relative WEIGHT 



(and range): 

 per cent 



0.72 (0.56 

 0.70 (0.55 

 0.68 (0.63- 

 0.72 (0.72 

 0.70 (0.55 

 0.55 (0.44 

 0.56 



0.57 (0.57 

 0.50 



0.44 (0.40^ 

 0.50 (0.47 

 0.46 (0.37 



0.93) 

 ■0.84) 

 ■0.85) 

 -0.72) 

 -0.83) 

 -0.68) 



-0.58) 



-0,48) 

 ■0.52) 



-0.56) 



■" Body-weight of controls at 10 weeks too high for comparison. 



