THE BLOOD. 59 



on coagulation is always smaller than the amount of fibrinogen from 

 which the fibrin is derived, and we always find a small amount of 

 globulin substance in the solution. It is therefore not improbable 

 that the coagulation of fibrin, in accordance with the views of DENIS, 

 is a splitting process in which the soluble fibrinogen is split into an 

 insoluble albuminous body, the fibrin, which forms the chief mass, 

 and a soluble globulin substance, which is only formed in small 

 amounts. The globulin substance, which is called "fibrin globulin " 

 by the author, coagulates at -|- 64 C. and has the following com- 

 position : 52.70$ ; H 6.98$ ; N 16.06$. 



The coagulation of the blood consists chiefly in the conversion 

 of the fibrinogen of the plasma into fibrin. The coagulation of the 

 blood is a much more complicated process than the coagulation of 

 a fibrinogen solution, inasmuch as the first involves other important 

 questions, as, for instance, the reason for the blood remaining fluid 

 in the body, the origin of the fibrin ferment, and the importance of 

 the form-elements in the coagulation. A fuller discussion of the 

 various hypotheses and theories concerning the coagulation of the 

 blood must therefore be given later. 



Serum Globulin, also called paraglobulin (KiJHNE), fibrino- 

 plastic substance (ALEX. SCHMIDT), serum casein (PANUM), fibrine 

 soluble (DENIS), occurs in the plasma, serum, lymph, transudations 

 and exudations, in the white and red corpuscles, and probably in 

 many animal tissues and form-elements, though in small quantities. 

 It is also found in the urine in many diseases. 



Serum globulin has the general properties of the globulins. In 

 a moist condition it forms a snow-white flaky mass neither tough 

 nor elastic. The essential differences between serum globulin and 

 fibrinogen are the following: Serum-globulin solutions are only 

 incompletely precipitated by adding NaCl to saturation, and not 

 precipitated at all by an equal volume of a saturated common-salt 

 solution. The coagulation temperature is, with 5-10$ NaCl in 

 solution, -j- 75 C. It is completely precipitated by MgS0 4 in sub- 

 stance added to saturation, as also by an equal volume of a sat- 

 urated solution of ammonium sulphate. The specific rotary power, 

 according to FREDEEICQ, for serum globulin (from-ox blood) solu- 

 tions containing salt is <x(D) = 47.8. 



