464 



CIRCULATION OF BLOOD AND LYMPH. 



It appears from these figures that there is no proportion between 

 the size of an animal and the amount of mean arterial pressure. It 

 is probable that there may be a general relationship between the 

 size of the animal that is, the size of the heart and the amount 



C-M 



ISO 



I'm 



LOO 



JVL 



Fig. 189. Curve showing the results of actual measurement of systolic, diastolic, and 

 mean pressure (lateral pressures) along the a9rta and femoral of the dog. The branches 

 through which the lateral pressures were obtained are indicated as follows: Sb, Left sub- 

 clavian; C-M, celiac and superior mesenteric; R, left renal; F, left femoral (Ellenberger 

 and Baum), external iliac; P, profunda branch of femoral; S, saphena. The pressure in 

 millimeters is given along the ordinates to the left. It will be noted that the mean and 

 the diastolic pressures remain practically the same throughout the descending aorta and 

 in-to the femoral. The systolic pressure shows a marked increase at the lower end of 

 the aorta and then falls off rapidly. The pulse pressure at the inferior end of the descend- 

 ing aorta is much larger than at the arch. (Dawson.) 



of pulse pressure or the oscillation of pressure with each heart beat, 

 but sufficient data are not at hand to determine this point. As 

 we pass from the aorta to the smaller arteries the mean pressure 

 decreases somewhat, although not very rapidly, while the pulse 

 pressure decreases also and to a more noticeable extent. 



