VASCULAR SYSTEM. 123 



foramen into contact, as to close it. Again, the vital forces 

 of the left auricle may, after birth, reject black venous 

 blood; this is the elective operation of the vital forces of 

 the different organs. 



Q. You have stated the great development of the cere- 

 bral arterial system in infancy, where does it predominate 

 at puberty? 



A. In the genital organs and the lungs. 



Q. Where is vitality most active in adult life? 



#. In the viscera of the abdomen. 



Q, How many kinds of bodily growth are there? 



t#. Growth in height, and thickness; the first ends 

 about the eighteenth year, the second continues till the 

 fiftieth year. When the growth in thickness ceases, the 

 calibres of the arteries no longer increases, and the arte- 

 rial development has no local preponderance. 



Q. What takes place in the arterial system of old age? 



JL. The blood is sent with diminished force to the small 

 arteries; they gradually close and are obliterated. 



Q. What are the two great offices of the circulation of 

 red blood? 



#* To impart nutrition, and excite the organs by the 

 arterial motion. 



Q. -Under what circumstances are the arteries acci- 

 dentally developed? 



#. When their natural course is obstructed ; in tumours; 

 in pregnancy. Painful tumours, or those in which there 

 is an exalted animal sensibility, produce this development 

 more than indolent tumours. 



Q. Does Beclard believe that the arteries do not possess 

 sensible organic contractility? 



