5 2 4 



TEXT-BOOK OF PHYSIOLOGY. 



known as sensor end-nuclei. Though once regarded as the centers 

 of origin of the sensor nerves, they are now regarded as the centers 

 of origin of axons which pass upward to the cortex of the cerebrum, 

 where they also come into physiologic relation with sensor nerve- 

 cells. 



FIG. 236. GANGLIA OF ORIGIN OF THE 

 SENSOR CRANIAL NERVES, i. Tri- 

 geminal (ganglion of Gasser). 2. 

 Nerve of Wrisberg. 3. Auditory 

 (ganglion of Scarpa). 4. Glosso- 

 pharyngeal (ganglion of Andersch). 

 5. Pneumogastric (ganglion plexi- 

 formis). {After Moral and Doyon.) 



FIG. 237. NUCLEI OF ORIGIN OF THE 

 MOTOR CRANIAL NERVES. i. 

 Motor oculi. 2. Patheticus. 3. 

 Motor root of the trigeminal. 4. 

 Abducens. 5. Facial. 6. Mixed 

 nucleus for efferent fibers of the 

 glosso-pharyngeal vagus and spinal 

 accessory. 7. Hypoglossus. 8. 

 Spinal accessory. 9. Spinal 

 nerves. (After Moral and Doyon.) 



The axons in both of these classes of nerves thus originate in the 

 cells of the central nerve system and continue upward to the cere- 

 brum, the primary afferent path. 



The motQ nerves which have their origin in the cells of the gray 

 matter beneath the aqueduct of Sylvius and beneath the floor of the 

 fourth ventricle are in physiologic relation with nerve-cells in the 



