120 EFFECTS OF INANITION IN THE PREGNANT ALBINO RAT. 



in Group I agrees with the observations of Jackson (1909) that in the human fetus 

 the relative weight of the stomach with contents is at first but little larger than 

 that for the empty stomach. 



The full stomach in my test rats forms 1.9, 1.5, 1.5, 1.3, and 1.0 per cent of the 

 body-weight in Groups I to V, respectively (computed from table 5). Thus the 

 relative weight of the full stomach is greater in the smaller test rats, while the con- 

 verse is true of the prenatal controls. 



The absolute weight of the full stomach is variable, averaging 3.7 per cent less 

 in the test rats than in prenatal controls (see table 5) . 



The empty stomach in my prenatal controls forms 0.31, 0.37, 0.39, 0.37, and 

 0.38 per cent oi the body-weight in Groups I to V, respectively (computed from 

 table 5) . Thus the relative weight of the empty stomach in the prenatal controls is 

 slightly less than that of the normal newborn rat, the difference in relative weight 

 being most marked in Group I. 



In my test rats the empty stomach forms 0.34, 0.38. 0.40, 0.38, and 0.39 per 

 cent of the body-weight in Groups I to V, respectively (computed from table 5). 

 Thus, with the exception of Group I, there is very little difference in the relative 

 weight of the stomach in the test rats and in the prenatal controls. 



In the largest rats (Group V) the stomach (in both the test rats and prenatal 

 controls) has practically the same relative weight as in the normal newborn rat. 

 Thus the normal relative weight of the stomach is disturbed very little by prenatal 

 inanition. The stomach in the test rats shows an average of 5.6 per cent in absolute 

 weight above the prenatal norms. The difference is most marked in Group I (the 

 smallest rats), where the absolute weight in the test rats is 15 per cent above that of 

 the controls (table 5) . 



Pancreas. — In postnatal inanition experiments on rats no direct observations 

 have heretofore been made on the weight of the pancreas. Therefore no compar- 

 isons can be made with postnatal results. 



Hatai (1918) gives the weight of the pancreas in the newborn rat as 0.0193 

 gram, or 0.45 per cent body-weight, 4.25 grams. In my normal newborns the weight 

 of the pancreas is 0.0224 gram, or 0.45 per cent body-weight, 4.92 grams. 



In my prenatal controls the weight of the pancreas forms 0.35, 0.38, 0.35, 0.45, 

 and 0.42 per cent of the body-weight in Groups I to V, respectively (computed from 

 table 5). Thus, in the smaller prenatal controls (fetuses) the pancreas has a lower 

 relative weight than in the larger rats (fetuses) in which the pancreas has approx- 

 imately the same relative weight as in the normal newborn rat. 



In my test rats the average weight of the pancreas forms 0.31, 0.37, 0.42, 0.37, 

 0.46 per cent of the body-weight in Groups I to V, respectively (computed from 

 tableS). Thus in the test rats, as in the prenatal controls, the pancreas in the smaller 

 rats forms a lower percentage of body- weight than in the larger rats, in which the 

 pancreas has a relative (percentage) weight about the same as that in the normal 

 newborn rat; but the weight of the pancreas is extremely variable in its indi- 

 vidual weight and average absolute weight throughout all the groups (see table 5). 



