NERVOUS SYSTEM. 95 



*ft. Nervous anastomoses, vascular communications, or 

 the continuity of cellular and mucous tissue. 



Q. What is the most rational division of sympathies? 



A. Into those which actuate animal and organic sensi- 

 bility and contractility. 



Q. Can you explain the sympathies of animal sensibi- 

 lity? 



t/f?. They depend on an irregularity or derangement of 

 perception in the brain, by which, an impression made on 

 one part, is referred to another; nervous communication is 

 not necessary to this. 



Q. On what does the sympathy of animal contractility 

 depend ? 



tf. The impression is made on the muscles through the 

 brain. 



Q. Are nerves, when cut, reproduced? 



A. They are, as other parts are. 



Q. How are external sensations transmitted ? 



#. Uniformlyifcy the nerves. The internal sensations 

 are conveyed in an unknown manner. 



Development of the Nervous System of Animal Life. 



Q. What is the state of the brain and nerves in the 

 foetus? 



#. Inactive, but much developed. The nerves in in- 

 fancy are much larger in proportion to the body, than 

 those at adult life ; so likewise is the brain. 



Q. What remarkable change takes place in the animal 

 nervous system at birth? 



/?. In foetal life it is supplied with black blood, at the 

 commencement of independent life it has red blood. 



