RED BLOOD CORPUSCLES 37 



The most abundant salt of the plasma is sodium chloride. 

 It forms from 60 to 90 per cent, of the total mineral matter of 

 plasma. Potassium chloride is present in much smaller amount. 

 Other salts are the carbonates, sulphates and phosphates. 



Corpuscles. 



Suspended in the plasma of the blood we have a cellular formed 

 element moving and functionating. This element is the corpus- 

 cular element and is composed of (a) the red blood corpuscles, (b) 

 the white blood corpuscles, (c) the blood platelets. 



(a) Red Blood Corpuscles or Erythrocytes. 



General Description. The red blood corpuscles are circular, 

 bi-concave discs with rounded edges. They are from 7 to 8 

 micra in diameter and 2 micra in thickness, so can only be seen 

 with the aid of the microscope. When looked at singly they 

 appear to have a yellowish-green color, collectively they are 

 red. 



Number. In males there are about 5,000,000 red cells to a 

 cubic millimeter; in females about 4,500,000. The proportion 

 of reds to whites is one white to every 500 red. 



Origin and Destruction. The red corpuscles are continu- 

 ally being destroyed in the body. It appears that this destruction 

 occurs principally in the liver. As the red cells are thus de- 

 stroyed it is natural to look for a place of manufacture. In the 

 embryo we find that this generation takes place in the liver and 

 in the spleen; in the adult it seems that the manufacture takes 

 place only in the red marrow of the bones. 



The red corpuscles are formed from colored, nucleated cells 

 called hemoblasts. 



Constituents of Red Blood Corpuscles. The red blood cor- 

 puscles are made up of 65 per cent, water and 35 per cent, solids. 

 The principal solid constituents are (a) hemoglobin (oxyhemo- 



