TEEFACIAL NERVE. 199 



eibility is complete after division of the nerve behind the 

 Gasserian ganglion, these results may not follow. Xor are 

 they explained by deficiency in the lachrymal secretion, for 

 they are not observed when both lachrymal glands have 

 been extirpated. They are not due to exposure of the eye- 

 ball, for they do not follow upon section of the facial. Xor 

 are they due simply to an enfeebled general condition, for, 

 in the experiment we have detailed, the animal died of inani- 

 tion after section of the nerve, without any evidences of in- 

 flammation. In view of the fact that section of sympathetic 

 filaments is well known to modify the nutrition of parts to 

 which they are distributed, producing congestion, increase in 

 temperature, and other phenomena, it is rational to infer 

 that the modifications in nutrition which follow section of 

 the fifth after it receives filaments from the sympathetic sys- 

 tem, not occurring when these sympathetic filaments escape 

 division, are to be attributed to lesion of the sympathetic, 

 and not the division of the sensory nerve itself. 



A farther explanation is demanded for the inflamma- 

 tory results which follow division of the sympathetic fila- 

 ments joining the fifth, inasmuch as division of the sym- 

 pathetic alone in the neck produces simply exaggeration of 

 the nutritive processes, as evidenced chiefly by local increase 

 in the animal temperature, and not the well-known phenom- 

 ena of inflammation. 



It has been remarked by Bernard, that the " alterations 

 in nutrition appear more promptly in animals that are enfee- 

 bled." ' Section of the small root of the fifth, which is un- 

 avoidable when the nerve is divided in the cranial cavity, 

 generally interferes so much with mastication as to influence 

 seriously the general nutrition ; and this might modify the 



1 BERNARD, Lemons sur la physiologieet la pathologic du systtmc neiveux, Paris, 

 1858, tome ii., p. 62. Barnard (op. cit., p. 518), in discussing the effects upon 

 calorification and nutrition of the face of division of the sympathetic in the neck, 

 states that " the effects of calorification of the great sympathetic may be trans- 

 formed into inflammatory phenomena when the animal becomes enfeebled." He 

 divided the sympathetic with the pneumogastric in the neck of a dog, on the 



