SUBMAXILLARY REGION 



note the mucous membrane stretching from the tongue to 

 the gum of the lower jaw ; then identify the various muscles. 

 The hyoglossus, a portion of which was previously visible 

 behind the mylo-hyoid, is fully exposed. It is a quadrangular 

 sheet of fleshy fibres which extends from the hyoid bone to 

 the side of the tongue. Mark its position, because all the 

 structures in this region have a more or less intimate relation- 

 ship to it. Thus, posterior and also superficial to its upper 

 part, the stylo-glossus muscle will be recognised, whilst anterior 



Stylo-glossus 



Stylo-pharyngeus 

 V,,-. / Glosso-pharyngeal 

 nerve 



Stylo-hyoid 

 'ligament 



i Lingual nerve 



Deep part of submaxillary gland 

 Submaxillary ganglion 



Submaxillary duct (Wharton's) 



Cut edge of mucous membrane 

 "lublingual gland 



/ Sublingual artery 



Genio- 



/glossus 



Genio-hyoid 



Lingual artery 

 Middle constrictor 



Lingual artery 



Hypoglossal nerve 

 Supra-hyoid artery 



FIG. 115. Dissection of Submaxillary Region. 



to it are the genio-glossus and the genio-hyoid. The genio- 

 hyoid muscle occupies the antero-inferior part of the region, 

 whilst the anterior part of the genio-glossus is seen in the 

 interval between it and the hyoglossus. Upon the surface of 

 the hyoglossus, the lingual and hypoglossal nerves, the con- 

 necting loop between them, the deep portion of the sub- 

 maxillary gland with the submaxillary duct, and the submaxillary 

 ganglion are to be dissected. The lingual nerve occupies the 

 highest level, and passes anteriorly upon the muscle near its 

 insertion into the tongue. The hypoglossal nerve, with its 

 vena comitans, crosses it close to the hyoid bone, whilst the 



