THE CRANIAL SERVES. 



nerves, but mainly offsets of distribution to muscles connected with the hyoid bone 

 and larynx, and to the muscles of the tongue. 



A. Branches of communication. 



- Close below the skull the hypoglossal nerve is united by a filament with the 

 superior cervical ganglion of the sympathetic, by one or more twigs with the loop 

 between the first and second cervical nerves, and with the ganglion of the trunk of the 

 vagus by fibres which pass between the two nerves where they are in close connection 

 with one another. 



As the nerve turns round the occipital artery, it is joined by the small lingual 

 branch of the vagus (p. 265) ; and in the submaxillary region, it is connected with 





Fig. 183. VIEW OP THE DISTRIBUTION OP THE SPINAL ACCESSORY AND HYPOGLOSSAL NERVES. (From 

 Sappey, after Hirschfeld and Leveille.) | 



1, lingual nerve ; 2, pneumo-gastric nerve ; 3, superior laryngeal (represented too large) ; 4, external 

 laryngeal branch ; 5, spinal accessory ; 6, second cervical ; 7, third ; 8, fourth ; 9, origin of phrenic 

 nerve ; 10, nerve to subclavius ; 11, external anterior thoracic nerve : 12, hypoglossal nerve ; 13, 

 descending cervical nerve ; 14, communicating cervical nerve ; 15, 16, 18, 19, branches from the plexiform 

 union of these nerves to the sterno-hyoid, sterno-thyroid and omo-hyoid muscles ; 17, branch to the 

 anterior belly of the omo-hyoid muscle ; 20, branch, to the thyro-hyoid muscle; 21, communicating 

 twigs from the hypoglossal to the lingual nerve ; 22, terminal branches of the hypoglossal nerve. 



the lingual branch of the fifth nerve by one or two slender loops over the fore part 

 of the hyo-glossus muscle. 



B. Branches of distribution* 



Vascular branches. These are one or two slender twigs which leave '''the 

 hypoglossal nerve close below the skull and pass to the mesial aspect of the internal 



