10 



after it lias been cut in the neck, the vessels of the face and of 

 the ear after a certain time begin to contract ; their contraction 

 increases slowly, but at last it is evident that they resume their 

 normal condition, if they are not even smaller. Then the tem- 

 perature and the sensibility diminish in the face and the ear, and 

 they become in the palsied side the same as in the sound side. 



When the galvanic current ceases to act, the vessels begin to 

 dilate again, and all the phenomena discovered by Dr. Bernard 

 reappear. 



I conclude, that the only direct effect of the section of the 

 cervical part of the sympathetic, is the paralysis and conse- 

 quently the dilatation of the bloodvessels. Another evident con- 

 clusion is, that the cervical sympathetic send motor nerve fibres 

 to many of the bloodvessels of the head.* 



8. Nearly all physiologists believe that the secretion of the 

 gastric juice is stopped after the section of the two pneumo- 

 gastric nerves. It is difficult to solve the question by experi- 

 ments on warm-blooded animals, because they die too quickly after 

 the section of the vagi. But it is not so with frogs. I have 

 found that they are able to live perfectly well either after the 

 extirpation of the medulla oblongata, or after the extirpation of 

 the ganglia of the par vagum. In both these cases I have found 

 that digestion continues to be performed. Consequently, if the 

 gastric juice is necessary to digestion, it is certain that this 

 liquid is secreted.f 



* My experiments prove, also, that the bloodvessels are contractile, and 

 that the nerves are able to put them in action. I have also to remark that 

 it is a fact, well established by Budge and Waller, that the cervical sympa- 

 thetic is one of the motor nerves of the iris, and that the spinal cord is the 

 origin of the nerve-fibres going from the sympathetic to the iris. Some 

 experiments, which I intend to perform again, appear to prove that the 

 same parts of the spinal cord which give origin to some of the motor nerve- 

 fibres of the iris, originate also the motor nerve-fibres going from the cer- 

 vical sympathetic to the vessels of the head. Another conclusion is to be 

 drawn from the results obtained by Budge, Waller, Bernard and myself; it 

 is that the cervical sympathetic, instead of receiving its fibres from upwards 

 to give them downwards, received them downwards and distributes them 

 upwards. 



~j~Comptes rendus de 1'Acad. des Sciences. Paris, 1847. T. xxiv. p. 

 363-64. 



