BLOOD. 



349 



Composition of Blood-plasma (1000 parts). 1 



Composition of Blood-serum (1000 part8). 



Horse. 



Horse. 



Man. 



Ox. 



Water 917.6 



Solids 82.4 85.97 92.07 89.65 



Total proteids 69.5 72.57 76.20 74.99 



Fibrin (derived from the fibrinogen) 6.5 



Paraglobulin 38.4 45.65 31.04 41.( 



Serum-albumin 24.6 26.92 45.16 33.30 



Extractives and salts | 12.9 13.40 15.88 14.66 



Red Corpuscles, Human Stood (Ho-ppe-Seyler). 



I. II. 



Oxyhaemoglobin 86.8 94.3 per cent. 



Proteid (and nuclein ?) 12.2 5.1 " 



Lecithin 0.7 0.4 " 



Cholesterin 0.3 0.3 " 



Leucocytes, Thymus of Calf (Mien/eld). 

 In the total dry substance of the corpuscles, which was equal to 11.49 per cent., there was contained 



Proteid 1.76 per cent. 



Leuco-nuclein 68.78 " 



Histon 8.67 " 



Lecithin 7.51 " 



Fat 4.02 " 



Cholesterin 4.40 " 



Glycogen 0.80 " 



The extractives present in the blood vary in amount under different conditions. 



Average estimates of some of them, given in percentages of the entire blood, 



have been reported as follows : 



Dextrose (grape-sugar) 0.117 per cent. 



Urea 0.016 " 



Lecithin 0.0844 " 



Cholesterin 0.041 " 



Proteids of the Blood-plasma. The properties and reactions of proteids 

 and the related compounds, as well as a classification of those occurring in the 

 animal body, are described in the section on the Chemistry of the Body. 

 This description should be read before attempting to study the proteids of 

 the plasma and the part they take in coagulation. Three proteids are usually 

 described as existing in the plasma of circulating blood namely, fibrinogen, 

 paraglobulin, or, as it is sometimes called, " serum-globulin/' and serum-albu- 

 min. The first two of these proteids, fibrinogen and paraglobulin, belong to 

 the group of globulins, and hence have many properties in common. Serum- 

 albumin belongs to the group of so-called "native albumins" of which egg- 

 albumin constitutes another member. 



Serum-albumin. This substance is a typical pro'teid. Its elementary com- 

 position, according to Hammarsten, is as follows : 



c H N s o 



53.06 6.85 16.04 1.80 22.26 



These figures can be regarded as approximate only. Serum-albumin shows the 

 1 Hammarsten: A Text-book of Physiological Chemistry, 1893 (translated by Mandel). 



