ORIGIN OF CEREBRAL NERVES. 319 



5. Trigeminal (n. trigeminus) motor and common sensory. 



6. Abducent (n. abducens) motor. 



7. Facial (n. facialis) motor. 



Intermediate (n. intermedius) special sense of taste, 

 secretory and trophic. 



8. Acustic (n. acusticus) special senses of hearing and equi- 



librium. 



9. Glossopharyngeal (n. glossopharyngeus) Special sense of 



taste, common sensory, secretory, trophic and motor. 



10. Vagus (n. vagus) motor, vaso-motor, viscero-motor, inhibi- 



tory, secretory, trophic and common sensory. 



n. Accessory (n. accessorius) motor. 



12. Hypoglossal (n. hypoglossus) motor. 



AU cerebral nerves are connected with the brain and, when their 

 functions were not understood, these points of connection were 

 indiscriminately called origins; but with our present knowledge 

 of the functions and development of the pure sensory and the 

 mixed nerves such use of the term "origin" is not admissible. 

 Pure sensory nerves and the sensory roots of mixed nerves take 

 their origins from ganglia situated wholly outside the brain. From 

 those ganglia the dendrites grow outward to the peripheral dis- 

 tribution of the respective nerves; the axones grow centrally into 

 the brain, where they arborize and end in groups of cell-bodies 

 forming nuclei. Such nerves conduct impulses from the per- 

 iphery to these nuclei, hence the name applied to them is terminal 

 nuclei (nuclei terminates). See the blue nuclei, Fig. 96. The 

 motor nerves and the motor roots of mixed nerves take their 

 origins inside the brain from groups of cell-bodies also called 

 nuclei. The axones grow outward from these latter nuclei toward 

 the periphery; they conduct impulses from the nuclei to the mus- 

 cles or to the secreting cells hi their respective areas of distribution, 

 hence the nuclei of motor nerves and motor roots are genetic nu- 

 clei (nuclei origines). See the red nuclei, Fig. 96. Thus it is seen 

 that the brain connection of a motor nerve is its true origin, while 

 this connection is the real termination of a sensory nerve. 



