THE COMPOSITION OF THE RED CORPUSCLES 135 



ing blood to clot in large test-tubes or by subjecting test-tubes of whipped 

 blood to the action of a centrifugal machine for some time. Serum is chemi- 

 cally very much the same as plasma except that it has lost the fibrinogen in 

 the process of clotting and has gained the by-products of that process throm- 

 bin, thrombokinase, and fibrin-globulin. The salts of serum are practically 

 those of plasma. 



The Composition of the White Corpuscles. The white corpuscles 

 are comparatively undifferentiated cellular elements, hence possess the 

 chemical composition of protoplasm. Lillienfeld has made an analysis 

 of the leucocytes of thymus gland from the calf, which contain 1 1 . 49 per 

 cent, of solids, as follows: 



In 100 Parts of Dry Substance of Corpuscles of Calf. 



Per cent. 



Protein 1.76 



Leuconuclein 68 . 78 



Histon 8.76 



Lecithin 7.51 



Fat 4.02 



Cholesterin 4-4 



Glycogen 0.80 



96.03 



The most noteworthy substance in this table is the nucleohiston content, 

 first isolated by Kossel and Lillienfeld. Beside the substances in the above 

 table, the white corpuscles contain salts of potassium, sodium, calcium, and 

 magnesium. The potassium phosphate is present in greatest amount. 



The Composition of the Red Corpuscles. Analysis of moist blood 

 corpuscles shows the following results: 



Water 68.8 per cent. 



Solids- 

 Organic 30. 388 \ 



Mineral 0.812 / 3 



100. o 



Of the solids the most important is the respiratory pigment, hemoglobin, 

 the substance to which the blood owes its color. It constitutes, as will be 

 seen from the appended table, more than 90 per cent, of the organic matter 

 of the corpuscles. Besides hemoglobin the corpuscles contain protein and 

 fatty matters, the former chiefly consisting of globulins, and the latter of cho- 

 lesterol and lecithin. 



In 100 parts of organic matter are found: 



Hemoglobin 90 . 54 per cent. 



Proteins 8.67 per cent. 



Fats 0.79 per cent. 



