MILLER — CONTRIBUTIONS FROM ANATOMICAL LABORATORY. 233 



as other muscles adjoining. The Opthalmic nerve could be traced 

 to the Gasserian ganglia as well as the branch in question, but 

 I could not find, as already stated, a nerve arising from a sep- 

 arate origin that would correspond to the Vlth, and there were 

 no nerve fibres that could have arisen from the roof of the fourth 

 ventricle. 



V. Trigeminal. This is one of the largest of the cranial 

 nerves. The trigeminal arises from the cephalo-lateral angle 

 of the metencephalon. It runs forward at quite a sharp angle 

 with the brain and just before it penetrates the brain case it 

 joins the Gasserian ganglion from which two main branches pass 

 out, the ophthalmic and maxillo-mandibularis. 



VII. Facial. This arises in conjunction with and anterior 

 to the Vlllth on a line parallel to the Vth and a short dis- 

 tance caudal. Xear its origin it divides into two main branches, 

 one of which joins the Gasserian ganglion, the other and larger 

 continuing with the Vlllth nerve for a short distance and then 

 separating. 



VIII. Auditory. This is a thick and very short nerve, which 

 shortly after separating from the Vllth divides into two main 

 branches, which join the auditory vesicle. It extends out at 

 right angles from the brain and, in its final branching, becomes 

 like a brush. 



IX. Glossopharyngeal. This arises by a single origin on a 

 line parallel with the Vllth and a short distance posteriorly. 

 It then proceeds caudal at a sharp angle with the brain for a 

 short distance and unites with the Vagus. 



X. Vagus. This arises from two separate origins about on 

 a line with each other, and with the IXth at a place opposite 

 the middle of the fourth ventricle. The posterior root is the 

 smaller and unites with the anterior root just before the 

 IXth joins them. The joint root thus formed runs into the 

 ganglion of the Vagus. 



