MYOLOGY 79 



fasciculi blend with those of the mylo-hyoideus; internally with the 

 lar3aix at the upper part. 



Action. — To raise the trachea and hyoid apparatus against the 

 pharynx. 



THE MUSCLES OF THE TONGXnE 



Mylo-hyoideus Stylo-hyoideus 



Genio-hyoideus Cerato-hyoideus 



Sterno-hyoideus Depressor-glossus 



Cerato-glossus Hyoideus transversus 



Mylo-hyoideus. Location. — The forepart of the inter-ramal 

 space. 



Origin. — From the inner side of the lower jaw at a point just 

 above the lower border and the inturned edge o'f the homy sheath of 

 the beak. 



Insertion. — By aponeurosis to the under side of the hyoid, on the 

 median line between the first and the second basi-branchial. 



Shape. — ^Thin, flat, and delicate. 



Relations. — Inferiorly with the skin. Thin and rather broad, it 

 meets its fellow of the opposite side. Laterally with the rami 

 of the jaw. Superiorly with the hyoid apparatus. 



Action.' — Lifts the tongue upward against the roof of the mouth. 



Stylo-hyoideus (Fig. 17, No. B, 6). Location. — Supero-posterior 

 to the hyoid apparatus. 



Origin. — From the outer portion of the articular enlargement of 

 the lower jaw. 



Insertion. — By a tendon to the basi-branchial of the thyro-hyal. 



Shape. — ^A long transversely flattened fasciculus. 



Relations. — Supero-posterior part of the hyoid apparatus along 

 side the genio-hyoideus and the cerato-hyoideus. 



Action. — Singly, pulls the tongue to one side; acting with its 

 fellow, pulls the tongue upward. 



Genio-hyoideus (Fig. 9, No. 7). Location. — Supero-posterior to 

 the hyoid apparatus. 



Origin. — From the anterior portion of the inner side of the lower 

 jaw. 



Insertion.- — ^To the middle of the outer side of the basi-branchial 

 of the corner of the os hyoides which cornu it completely envelops. 



Shape. — A long, rather thick fasciculus. 



Relations. — With the stylo-hyoideus and cerato-hyoideus. 



