198 THE BLOOD 



pigment, 48 grams of hemoglobin must be made available, i.e., about 

 one-tenth of the total amount of this substance ordinarily present in 

 an individual weighing 65 kilos and possessing about 3500 grams of 

 blood. Upon the basis of this calculation, the life of the circulating 

 red corpuscle may be said to be about ten days. Our long cherished 

 beliefs regarding the production of bile pigments, however, do not 

 agree with the views of Hooper and Whipple, 1 because it seems that 

 the liver possesses a certain inherent power to form pigment, thus 

 quite offsetting the calculation just given. A relatively severe -loss of 

 red corpuscles, which must be compensated for immediately, occurs 

 during the menstrual flow. Mix 2 states that 150 c.c. of blood are lost 

 during this period which are again reformed in the course of about 

 twenty-eight days. This necessitates the formation of 5000 cu. mm. 

 of blood in a day, 208 cu. mm. in an hour or 3.5 cu. mm. in a minute. 

 The total number of red corpuscles lost during this period, necessitates 

 the formation of 15,750,000 new cells in a minute. 



It seems that the disintegration of the red cells begins while they 

 traverse the general circulatory channels, but their absolute destruc- 

 tion and dissolution is restricted to two organs, namely, to the liver 

 and the spleen. Moreover, it is very probable that the former organ 

 possesses a much greater disintegrating power than the latter, which 

 belief may be substantiated by the following facts: 



(a) The liver is the place in which the hematin is changed into bile pigment, 

 and hence, an adequate supply of the former substance must always be kept on 

 hand. 



(6) The hepatic cells contain iron which is normally derived from the red 

 corpuscles. This fact may be established by treating a cross-section of this 

 organ with potassium ferrocyanid and acid alcohol, under which condition it 

 assumes a blue color. While a part of the iron is excreted, a part of it is reabsorbed 

 and may again be employed in the formation of new corpuscles. 



(c) The quantity of the biliary pigment may be increased by injecting hemo- 

 globin into the blood stream. 



(d) The deposition of iron in the liver may be increased experimentally by 

 inciting a greater destruction of the red cells. This can be done by introducing 

 toxic agents into the circulation. A disintegration of red cells also occurs under 

 pathological conditions, for example, in the course of certain anemias. 



(e) A deposition of hemoglobin crystals in the cells of this organ has been 

 observed. 



(/) The blood of the hepatic vein is said to contain fewer red cells than that of 

 the portal vein. 



(gf) The endothelial cells lining the capillaries of the liver, the so-called "Stern- 

 zellen," possess the power of taking up foreign particles and of rendering the red 

 corpuscles effete. 



A disintegration of the red corpuscles also occurs in the lymphoid 

 tissues and in the spleen. This conclusion is based upon the observa- 

 tion that red cells or pieces of them are found at times in the cytoplasm 

 of certain large cells, or macrophages, which are generally present in 



1 Am. Jour, of Physiol., xlii, 1917, 256. 



2 Boston Med. and Surg. Journal, 1892. 



