THE RED BLOOD-CORPUSCLES 943 



rapidly taken up by the phagocytes of the body. Sooner or later, how- 

 ever, every corpuscle undergoes disintegration, a process which is 

 generally ushered in by the ingestion of the corpuscle by some phago- 

 cytic cell. Thus in the haemolymph-glands and in the spleen we find 

 large cells which have englobed red corpuscles and in which we can 

 recognise pigment-granules obtained from their destruction. The 

 chief place of disintegration of the haemoglobin is certainly the 

 liver, i.e. the organ where the haematin is converted into bile- 

 pigment. Injection of haemoglobin into the circulation causes 

 increased secretion of bile-pigment. A section of normal liver im- 

 mersed in potassium ferrocyanide and then in acid alcohol shows the 

 presence of iron by the assumption of a blue colour. The amount of 

 iron which can be demonstrated in the liver in this way is enormously 

 increased by any condition which augments the rate of blood destruc- 

 tion. In the pathological condition known as pernicious anaemia, as 

 well as after poisoning by the injection of pyrogallic acid or toluylene 

 diamine, both of which agents cause a great destruction of red blood- 

 corpuscles, the liver on treatment in this way assumes a deep blue 

 colour. In some cases crystals of haemoglobin have been seen within 

 the nucleus of the liver-cell. In the destruction of the corpuscles the 

 haemoglobin is dissociated first into its protein and chromogenic 

 moieties ; the haemochromogen then loses its iron and is converted 

 into bile-pigment. The iron remains in the liver and is probably 

 retained in the body and utilised for the formation of the fresh haemo- 

 globin necessary for the newly forming red blood- corpuscles in the 

 bone-marrow. 





