THE NECK, ANTERIOR. 97 



Geniohyoglossus. Fig. 18. 



Origin. From the superior genial tubercle. 



Insertion. Into the body of the hyoid bone, the tongue 

 from its tip to its base just outside of the median plane, and 

 into the side of the pharynx. 



Nerve Supply. The hypoglossal. 



Action. To depress the lower jaw, to raise the hyoid 

 bone, to protrude the tongue (by its posterior fibres), to 

 depress and protrude the middle of the tongue (by its mid- 

 dle fibres), and to retract the tip of the tongue (by its ante- 

 rior fibres). 



Hyog-lossus. Figs. 17 and 18. 



Origin. From the body and great cornu of the hyoid 

 bone. 



Insertion. Into the substance of the posterior half of the 

 tongue external to the geniohyoglossus. 



Nerve Supply. The hypoglossal. 



Action. To depress the sides of, and retract the whole 

 tongue. 



Styloglossus. Fig. 18. 



Origin. From the front of the lower portion of the 

 styloid process. 



Insertion. Into the side of the tongue, interlacing with 

 the hyoglossus. 



Nerve Supply. The hypoglossal. 



Action. To retract the tongue and elevate its sides. 



Stylopharyng-eus. Fig. 18. 



Origin. From the inner surface of the base of the 

 styloid process. 



Insertion. Passing between the superior and middle 

 constrictor muscles, it is inserted into the posterior border 

 of the thyroid cartilage and wall of the pharynx. 

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