to draw up, by reflex action, more than double the weight 

 the animal could raise up by an action of its will before the 

 division of the cord. 2. After having divided the spinal cord in 

 the dorsal region on a mammal, I kill it by cutting the right 

 carotid artery. A few minutes after the cessation of reflex 

 action I inject blood by the opening made in the carotid. Then 

 life returns and with it the reflex faculty. 



All these facts demonstrate positively that the reflex faculty 

 is a vital property belonging to the spinal cord, and that its 

 source is in the nutrition which maintains the organization of that 

 nervous centre. 



b. Source of the vital property of the motor nerves. 



The independence of the motor nerves is denied by almost all 

 physiologists. They believe that the nervous centres are the 

 sources of the vital property of these nerves. They base their 

 opinion on this fact, that the motor nerves separated from the 

 nervous centres soon lose their property, as it has been seen by 

 Fontana, Haighton, Astley Cooper, Steinrueck, Mu'ller, Sticker, 

 Giinther, Schoen, Kilian, Stannius, Helmholtz, Martin-Magron 

 and others. 



But, in the first place, if the motor nerves of the warm-blooded 

 animals lose their vital property after having been separated 

 from the nervous centres, it is not less positive that they retain 

 it during several days. Secondly, if the vital property of the 

 motor nerves is exhausted by very energetic action, it re- 

 appears after a short time, although the nerves are separated 

 from the cerebro-rachidian centre, provided that the circula- 

 tion of blood continues in them. Thirdly, if the circulation 

 of blood is stopped in a limb in which the nerves have been 

 divided, it is found that the peripheric portion of the divided 

 nerves lose their vital property before the muscles. After the 

 nerves have been left dead, i. e., deprived of their vital property 

 for a quarter of an hour, half an hour, and even more, blood is 

 allowed to circulate anew in the limb. Then the vital property 

 of the cut nerves returns, and, to produce a muscular contrac- 

 tion, only a slight compression upon them is necessary.* If the 



*See Comptes rendus de 1'Aead. des Sciences. T. xxxii. Seance du 9 

 Juin, 1851. Gaz. Medic, de Paris. 1851. T. vi, p. 359. 



