The Blood and the Lymph. 81 



Liquid Blood and Coagulated Blood. The following 

 scheme shows the difference between the liquid blood and 

 the coagulated blood : - 



[Plasma . . . j Serum ; 1 



Liquid Blood | ( Fibrin | I Coagulated Blood. 



Corpuscles 



\ 



" Black-and-blue " Spots. A bruise often breaks some 

 of the capillaries without breaking the skin. Blood escapes 

 into the spaces in the skin or under it. This blood clots, 

 and the dark color shows through the skin. This clotted 

 blood is gradually absorbed and the color disappears. 



Amount of Blood. The blood constitutes about one 

 thirteenth of the weight of the body. In a body weighing 

 one hundred and fifty pounds this would be about six 

 quarts. 



Quantity of Blood in Different Organs. i . One fourth 

 is in the heart and the larger arteries and veins (including 

 those of the lungs). 



2. One fourth in the liver. 



3. One fourth in the skeletal muscles. 



4. One fourth in the other organs. 



The Lymph Spaces. We have seen that the capillaries 

 have very thin walls. Through their walls part of the 

 plasma of the blood soaks out, and is then called lymph. 

 It passes into irregular cavities in the tissue called lymph 

 spaces. Most of these lymph spaces are minute chinks or 

 crevices in the connective tissue of the different parts of 

 the body. 



The Lymph Tubes. Opening out of the lymph spaces 

 are irregular passage-ways called lymph capillaries, and 



