188 PHYSIOLOGY. 



The presence of iron in the spleen has long made this organ seem 

 a cradle to many physiologists where erythrocytes are born and 

 nourished. But the presence of this same element advances an 

 argument equally as strong in favor of the spleen being the grave 

 for these same bodies. 



Pathologically, masses of iron substances are found within the 

 spleen, liver, and red bone-marrow when abnormal disintegration 

 occurs, as in anwmia. 



COMPOSITION OF CORPUSCLES. 



A very notable fact about the red corpuscles is the low content 

 of water. Muscle and nerve tissue have about 75 per cent, of water. 

 The feeble metabolic changes in the corpuscle are shown by this 

 want of water. 



The red corpuscles consist of a stroma containing in its meshes 

 a peculiar proteid haemoglobin. Chemically they are made of 60 per 

 cent, of water and 36 per cent, of haemoglobin, the remaining 4 per 

 cent, representing the stroma, which is made up of lecithin, choles- 

 terin, and nucleo-proteid. The white corpuscles consist of solids 

 and water. The solids are gluco-proteids and nucleo-proteids and a 

 small amount of albumin and globulin. The protoplasm may also 

 contain glycogen and fat. The nucleus is made up of nucleo-pro- 

 teids, nuclein, and nucleic acid. The phosphorus content of the 

 nucleus is greater than that of the protoplasm. 



The table on the next page is the result of the analyses reported by 

 Halliburton. 



The other named constituents are common to the two kinds of 

 corpuscles. The mineral components are principally the chlorides 

 of potassium and sodium and the phosphates of calcium and mag- 

 nesium, the phosphates being in greater proportion. It will be 

 remembered that the sodium salts assume greater proportions in the 

 plasma. The nucleo-proteid obtained from the white corpuscles is 

 the precursor of the fibrin-ferment of coagulation. 



Haemoglobin. This is the pigment matter of the red corpuscles. 

 Haemoglobin is a proteid composed of globin, a histon, and haematin. 

 Its principal characteristics are: (1) its ability to combine chem- 

 ically with oxygen and other gases, (2) its spectroscopic phenomena, 

 (3) its crystallization, and (4) the fact of its containing iron. 



It is by virtue of the presence of this haemoglobin that the red 

 corpuscles are capable of performing the function of oxygen-carry- 

 ing carrying it from the external respiration in the lungs to the 



