NERVOUS STSTF 89 



JJ. It appears to differ, in different nerves, in consist- 

 ence, in the degree of moisture, in its colour, and other 

 particulars. 



Q. On what does the different sensibility of the various 

 parts depend ? 



*#. On the diversity of organization in the parts, on the 

 different organization of the nerves, and on the varying , 

 consistence and appearances of the medullary matter. 



Q. Is the nervous medulla a fluid? 



#. It resembles jelly, vjt is more like a fluid than a 

 solid. 



Q. Have the nerves cellular texture? 



*ft. In the interior of the brain and spine there is none. 

 When the nerves emerge from the cranium and spine, 

 they have much cellular tissue around the trunks, 'chords, 

 and filaments. Perhaps the nervous coat is the cellular 

 texture condensed. 



Q. How do the arteries supply the nerves ? 



<ft. Blood-vessels pass between the chords to supply the 

 filaments. 



Q. What influence has arterial blood on the nerves? 



*ft. It is to the nerve what blood is to every organ ; the 

 stimulus which supports and perpetuates functional power. 



Q. What influence has an increased determination of 

 blood to the nerves? 



.#. It increases nervous action, and when the determi- 

 nation is very great it overwhelms it. 



Q. How is the nervous medulla formed ? 



#. The arteries of the nerves deposite in the exha- 

 lents this nervous matter, which is then thrown out. 



Q. Then the nervous coat does not secrete it ? 



.#. The nervous coat has no more agency in secreting 





