Iron in combination with protein matter is found in considerable quantity in the cereal grains, but the greater part of it is in the germ and outer layers, and so is rejected in the making of the "finer" mill products, such as patent flour, polished rice, and new-process corn meal. In view of the part which the iron of the germ takes in the sprouting of the seed and the nutrition of the young plant, there is little room for doubt that it is of value also in the animal economy. To test the value of the iron in the outer layers of the grain Bunge * carried out the following experiment:

* Zeitschrift fur physiologische Chemie, Vol. 25, page 36 (1898). X

A litter of eight rats was divided into two groups of four each, one group fed upon bread from fine flour, the other upon bread made from flour including the bran. At the end of the fifth, sixth, eighth, and ninth weeks, respectively, one rat of each group was killed, and the gain in weight, the total amount of hemoglobin, and the percentage of hemoglobin in the entire body were determined. The average results were as follows:

Effect Of Feeding Different Kinds Of Bread On Growth And Iron Content Of Body In Experiments With Rats

Here the bran-fed rats not only made a much greater general growth, but developed both a greater amount and a higher percentage of hemoglobin. There can be no doubt that the iron and other ash constituents of the outer layers of the wheat were well utilized in these cases.