INORGANIC FOODS. 



381 



The remarkably small amount in milk of an inorganic element to which 

 we are accustomed to ascribe so great significance is very striking. Iron, 

 we know, forms an important constituent of the hemoglobin. Now in 

 comparing the composition of the ash of the suckling with that of the 

 milk, we found that the former contained considerably more iron. This 

 obliges us to draw the conclusion that the new-born animal is already 

 provided with a store of iron. The organism of the female can supply its 

 young with nourishment in two ways, at first through the placenta, and 

 later by way of the mammary glands. Evidently for some reason or other 

 in the case of iron the former method is preferred. In corroboration of this 

 Bunge * showed that the amount of iron contained in a new-born rabbit is 

 greatest at the time of birth, and decreases from day to day until it reaches 

 a minimum at the end of the period of lactation, increasing immediately 

 as soon as the animal changes to a food richer in iron. The following 

 table shows the results obtained by Bunge: 



Rabbits are fed on the milk of the mother for about three weeks. These 

 values show that the lowest iron content coincides with the end of the 



Z. physiol. Chem. 16, 173 (1892); 17, 63 (1893). 



