258 



MANUAL OF PHYSIOLOGY. 



The circulation might then be represented by a simple diagram 

 (Fig. 110) in which the direction of the current is indicated by 

 the arrows. L. H. shows the position of the left or systemic 

 pump, and S. the resistance in the systemic vessels. R. H. rep- 

 resents the pulmonary pump, and P. the second obstacle in the 

 circuit, viz., the vessels of the lungs. 



However, it must be remembered that the right and left pump- 



FIG. 112. 



FIG. 111. 



p.v. 



s.c. 



FIG. 111. Capillary Network of the Choroid of a Child of a few mouths old. (Cadiat.) 

 (a) Artery. (6) Vein, and capillary network intervening. 



FIG. 112. Diagram of the Circulation of the Blood and the absorbent vessels. For 

 details, see text. 



ing organs are fused into one viscus, which has two distinct and 

 separate channels for the passage of the blood through it. In 

 each system of blood vessels we have the same general arrange- 

 ment for the distribution and re-collection of the blood. 



In passing from either the right or left side of the heart the 

 blood flows into tubes called arteries, which divide and subdivide 



