motor nerves lose their property when they are separated from 

 the nervous centres, it is because they are then badly nourished. 

 Nerves as well as muscles must be exercised, in order to be 

 well nourished. 



c. Source of the muscular contractility. 



Although there are some facts which appear strongly to prove 

 that the vital property of the muscular tissue is independent of 

 the nervous system, many physiologists persist in their opposi- 

 tion to Haller's doctrine on this subject. Therefore I have 

 thought necessary to add new proofs to those already known, 

 and I have published many experiments, of which I shall relate 

 here only two of the most decisive.* 



1. The sciatic and the crural nerves having been resected, for 

 ten or twelve days, on a rabbit or a guinea-pig, I examine if these 

 nerves have completely lost their vital property, and if the 

 muscles are still contractile. When this has been ascertained, I 

 put a ligature around the aorta. Then muscular irritability dis- 

 appears after a certain time and cadaveric rigidity appears. 

 Three quarters of an hour or even an hour after the complete 

 disappearance of the muscular irritability, and the appearance of 

 the rigor mortis, I cut off the ligature, and I find, after ten or fif- 

 teen minutes, that the rigidity disappears and the contractility 

 reappears. I need not say that the nerves do not regain their 

 lost property. This fact clearly proves that the contractility is 

 given to the muscles by blood, i. e., by nutrition, and not by the 

 nervous system. 



2. Many experiments have shown to me that muscles paralyzed 

 for five days or a little more, in consequence of the division of 

 their nerves, remain much longer contractile after the death of the 

 animal than the non-palsied muscles. This would hardly be the 

 case if the contractility was given to muscles by the nervous 

 system. 



* See: Bulletin de la Soc. Philomat. 1847, p. 74. Gaz. Med. de Paris, 

 1851, t. vi. p. 619, and 1852, t. vii. p. 72. 



