I 9 2 



HEAD AND NECK 



whilst the deep part of the submaxillary gland and the sub- 

 maxillary duct (Wharton's) occupy an intermediate place. 

 Although the submaxillary ganglion is very small, its relations 

 are so precise that it is very easily found. By seizing the 

 lingual nerve and dissecting carefully in the interval between 

 it and the deep part of the submaxillary gland, the dissector 

 will expose the ganglion, and its roots and branches of dis- 

 tribution (Fig. 70). Upon the genio-glossus, anterior to the 



Inferior nasal concha (O.T. inferior turbinal) 

 M. pterygoideus internus f ^ 



M. pterygoideus externus, / / 



x^mJ^^mmmlmrsaMj I HMMMHM ' ' ' ^UBMOHMBl/l fl. fe. AfekWMMMMBBU 



-M. temporali 



M. styloglossus 



Inferior alveolar 



vessels and nerve 



Lingual nerve 



External 

 maxillary artery 

 Superficial part of 

 Libmaxillary gland 

 Submaxillary duct 

 Deep part 

 submaxillary gland 

 Hypoglossal nerve 



Lingual artery 



M. hyoglossus ' 

 M. mylohyoideus 

 Digastric tendon 



M. geniohyoideus 



Tongue 



Inferior alveo 

 vessels and n 

 in the mandib 

 ular cana' 

 External 

 maxillary arU 



M. mylohyoid 

 Lingual nerve 

 Deep part of 

 submaxillary gland 

 K Submaxillary duct 



Hypoglossal nerve 

 Lingual artery 

 M. digastricus 

 hyoglossus 



M. geniohyoideus 



FIG. 71. Frontal section through the Tongue and Submaxillary Region 

 in a plane posterior to the molar teeth. 



hyoglossus, the sublingual gland^ with its artery of supply 

 will be seen. If the stylo-hyoid and the posterior belly of 

 the digastric are displaced backwards, certain structures will 

 be seen passing under cover of the posterior margin of the 

 hyoglossus muscle. They are : (i) the glosso-pharyngeal 

 nerve, immediately below the stylo-glossus muscle ; (2) the 

 stylo-hyoid ligament, a little lower down ; and (3) the lingual 

 artery, close to the hyoid bone (Fig. 68). 



Musculus Hyoglossus. The hyoglossus is a quadrate, flat 

 muscle which arises from the whole length of the greater cornu, 



