GENERAL DISTRIBUTION, 



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General distribution. The greater number of the cranial nerves are entirely 

 confined in their distribution within the limits of the head, as in the case of the 

 first six pairs, the auditory, glosso-pharyngeal, and hypoglossal nerves. Of these, 

 the olfactory, optic, and auditory are restricted to their respective organs of sense ; 

 while the third, fourth, and sixth are exclusively motor nerves in connection with 



of the glosso-pharyngeal passing round the stylo-pharyngeus muscle after giving pharyngeal and 

 muscular branches ; 13', its distribution on the side and back part of the tongue ; 14, spinal accessory 

 nerve ; 14', the same after having passed through the sterno-mastoid muscle uniting with branches from 

 the cervical nerves ; 15, hypoglossal nerve ; 15', its twig to the thyro-hyoid muscle ; 15", its distribu- 

 tion to the muscles of the tongue ; 16, the descending cervical nerve giving a direct offset to the 

 anterior belly of the omo-hyoid muscle, and receiving the communicating branches 16 x , from the 

 cervical nerves ; 17, pneumo-gastric nerve ; 17', its superior laryngeal branch ; 17", external laryngeal 

 twig; 18, superior cervical ganglion of the sympathetic, uniting with the upper cervical nerves, and 

 giving at 18' the superficial cardiac nerve ; 19, the trunk of the sympathetic ; 19', the middle cervical 

 ganglion, uniting with some of the cervical nerves, and giving 19", the large or middle cardiac nerve ; 

 20, continuation of the sympathetic down the neck ; 21, great occipital nerve ; 22, third occipital. 



the muscles of the eyeball and the elevator of the upper eyelid. In the fifth or 

 trifacial nerve all the fibres derived from the large root, and connected with the 

 Gasserian ganglion, are entirely sensory in their function, and constitute the whole 

 of the first and second and the greater part of the third division of the nerve ; but 

 the last of these divisions has associated with it the fibres of the small or motor 

 root, so as to become in some degree a compound nerve. As a nerve of sensation 



