32 BIOLOGICAL ASPECTS OF HUMAN PROBLEMS 



cessation of metabolism in the tributary parts and 

 may even cause local death of the tissues. 



Perhaps the most significant likeness between a 

 federal state and a living body lies in the organiza- 

 tion of government. A central governmental organ- 

 ization of much complexity, connected with sub- 

 sidiary and similar organizations which ramify by 

 telegraph to the remotest governed parts, typifies 

 the central nervous system, the sympathetic systems 

 of ganglia, and other ganglionic systems connected 

 with nearly all parts of the body through the agency 

 of nerves and nerve fibers. Being continually in- 

 formed of the needs and conditions of all its parts 

 by means of stimuli carried centrally through sensory 

 pathways, the central nervous system makes ade- 

 quate response through the agency of those struc- 

 tures which preside over the muscles, the blood 

 vessels, the glands, and other parts of vital impor- 

 tance. Through the agency of consciousness the 

 muscular system is brought under a nice control and 

 innumerable fine adaptations are learned and con- 

 stantly practiced. By means of an indescribably 

 intricate and labile mechanism the nervous system 

 integrates and coordinates sensations and feelings in 

 such a way as to regulate beneficially the relations 

 not only of the various parts to each other, but also 

 of the entire individual to its surroundings. In 

 other words, the nervous mechanism typifies in its 

 activities at once a ministry of the interior and a 

 ministry of foreign affairs. Notable is the even 



