THE SUBMAXILLARY REGION. 73 



the deep portion of the subm axillary and the sublingual 

 glands, and the mucous lining of the floor of the mouth ; 

 posteriorly, the hyo-glossus muscle, extending from the 

 cornu of the hyoid bone to the side of the tongue, and 

 upon this muscle from below upwards lie (1) the ninth 

 or hypoglossal nerve; (2) Wharton's duct; (3) the gus- 

 tatory nerve with the submaxillary ganglion and chorda 

 tympani, and the inosculating branches of these two 

 nerves. Upon the cornu of the hyoid bone is seen the 

 trunk of the lingual artery just before it disappears 

 behind the hyo-glossus muscle. 



Arteries. The facial artery in this region passes 

 beneath the posterior belly of the digastric and stylo- 

 hyoid and submaxillary gland, and after giving off 

 branches to the gland, and the submental, it becomes 

 subcutaneous, about an inch in front of the angle of the 

 jaw. 



The lingual artery is deeper in its course and distribu- 

 tion, and is directed towards the hyo-glossus, and is at 

 first covered by the skin, platysrna, and fascia, and rests 

 on the middle constrictor ; after passing over the cornu 

 of the hyoid bone, it is crossed by the ninth nerve, the 

 digastric and stylo-hyoid muscles forming an arch over 

 it. It is next covered by the hyo-glossus, and lies on 

 the superior constrictor and genio-hyo-glossus muscles. 



The branches given off from it are, the hyoid, which 

 runs along the upper border of the hyoid bone; the 

 dorsalis linguae, supplying the dorsum of the tongue, 

 tonsil, and soft palate ; the sublingual, supplying its sub- 

 stance, and the ranine. 



Ligature of Lingual Artery. To place a ligature upon 

 the lingual artery, that portion of its coarse where it lies 

 upon the great cornu of the hyoid bone is selected, im- 



