640 NERVOUS SYSTEM. 



the small root of the fifth is divided as well as the large root, and the muscles of masti- 

 cation are paralyzed upon one side; but, with this exception, there is no paralysis of 

 motion, sensation alone being destroyed upon one side. 



FIG. 217. Operation for division of the ji/th nerve. (Bernard.) 



The calvarium and the cerebrum are removed in order to show the roots of the nerves and the direction of the instru- 

 ment used in section of the fifth. A, olfactory nerves ; B, optic nerves ; 0, motores oculorum communes ; D, 

 pathetici; E, fifth nerve ; H. blade of the instrument in the cranial cavity ; G, G' 1. 1', seventh pair of nerves ; 

 K, section of the spinal cord. 



i 



Immediate Effects of Division of the Trifacial. It is hardly necessary to discuss the 

 functions of the trifacial, after the statement of the effects which instantly follow upon 

 its division, taken in connection with its physiological anatomy. The nerve has never 

 been exposed in the cranial cavity in living animals ; but its branches upon the face and 

 the lingual branch of the inferior maxillary division have been operated upon and found 



