174 EQUINE PHYSIOLOGY. 



The solids of plasma are 



Fibrin, 1.91 



Albumin, 7.76 



Fats, 12 



Extractives, 40 



Soluble salts, 64 



Insoluble salts, 17 



10.10 



The Specific Gravity of the horse's blood is 1055, its Reaction 

 alkaline, and its Temperature 36.5 to 37.8 Cent. (Charles.) 



The corpuscles are found in two forms, the red and white. 



The red corpuscles are bi-concave disks, with no nuclei, tending 

 to adhere in rolls, with a diameter of .005 mm. They contain 

 the coloring matter, the haemoglobin, which in the horse contains 

 43 per cent, of iron, and also C, H, N, O, and S (Preyer). The 

 haemoglobin forms about 90 per cent, of the red disks (Smith). 

 Their function is to absorb and carry oxygen. 



The white corpuscles are much less numerous than the red, the 

 proportion being on an average one white to 300 red. They are 

 globular in shape and are o.oi mm. in diameter, and contain sev- 

 eral nuclei. They are derived from lymphoid tissue, and are 

 probably developed into red corpuscles. They have the power 

 of amoeboid movement by pushing out processes, and of passing 

 through the walls of vessels. . 



COAGULATION OF BLOOD. 



When blood is placed in a vessel after removal from the body, 

 it goes through a process called coagulation: First, in a few min- 

 utes a yellow scum appears on top, the huffy coat; second, the cor- 

 puscles settle to the bottom, forming a reddish layer. Then drops 

 of serum are seen on the sides and top. In 12 or 15 hours the 

 serum and clot are completely separated. 



The serum differs from plasma in not containing fibrin. 



The specific gravity of plasma is 1027-1028. 



Theory of Coagulation (Schmidt). 



Fibrinogen and fibrinoplastin, with the fibrin-ferment, derived 

 probably from white corpuscles, come together and cause co- 

 agulation. 



Coagulation is hastened by a temperature of 100 F., contact 



