Normal human liver tissue (external trauma) contains much more of these hemoglobin production factors than the normal control animal liver—the ratio being 162 to 100.

In this form of biological assay 42 gm. of animal liver or 26 gm. of human liver represent 1 gm. of potential hemoglobin.

A second group (Table 2) in which the viscera were practically normal except for atrophy, the cases presenting a good deal of arteriosclerosis and senile changes, shows a lower content of these hemoglobin production factors. The ratio of human to control here is 117 to 100. This is certainly the low limit of normal.

Acute fulminant infections reduce somewhat the store of these potent hemoglobin production factors in the human liver (Table 3). The average value is 117 as compared with 100 control but the more acute cases show the lower values.

Chronic intoxications show values which are close to the human normal—151 per cent. The liver content of hemoglobin producing factors shows very wide fluctuations in cases of thyrotoxicosis. Diabetes may be associated with rather low values.

There may be complete dissociation of the organic iron content and the concentration of hemoglobin production factors in the liver.