8o ANATOMY OF THE DOMESTIC FOWL 



Action. — Protrudes the tongue from the mouth. 



Cerato-hyoideus (Fig. 9, No. 8). (Synonym. — Kerato hyoideus.) 



Location. — Inferior to the hyoid apparatus. 



Origin. — ^By a delicate tendinous slip from the under side of the 

 shaft of the basi-hyal element of the hyoid-apparatus. 



Insertion. — To a small elevation on the under side of the anterior 

 end of the glosso-hyal. 



Shape. — ^A small round muscular fasciculus becoming tendinous in 

 its anterior half. 



Relations. — Superiorly with the hyoid apparatus. 



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

 fellow, depresses the tongue. 



Stemo-hyoideus. Location. — Inferior to the hyoid apparatus. 



Origin. — From the outer anterior surface of the thyroid bone of 

 the superior larynx. 



Insertion. — ^To the anterior part of the basi-hyal. 



Shape. — ^At first broad and rather fleshy, becomes contracted and 

 somewhat tendinous. 



Relations. — Inferior to the hyoid apparatus and superior larynx. 



Action. — When the larynx is fixed, acting alone deflects the tongue 

 laterally; acting with its fellow, depresses the tongue. If the base 

 of the tongue is fixed the two pull the larynx forward. Hence 

 muscles of deglutition. 



Depressor-glossus. Location. — Superior to the basi-hyal. 



Origin. — From the imder portion of the basi-hyal. 



Insertion. — To under part of the glosso-hyal. 



Shape. — Small, short. 



Relations.- — Superiorly with the basi-hyal and glosso-hyal bones. 



Action. — Depresses the tip of the tongue and elevates the base. 



Cerato-glossus. Location. — On the upper Jiortion of the cornu 

 of the hyoid. 



Origin. — One-half of the surface of the first basi-branchial. 



Insertion. — To the upper side of the shaft of the cerato-branchial 

 element of the hyoid apparatus. 



Shape. — ^A small muscular fasciculus. 



Relations. — Supero-laterally to the cerato-branchial element. 



Action. — Elevates the cornua of the hyoid arches and presses them 

 against the skuU. 



Hyoideus Transversus (Fig. 9, No. 9 and 10). Location. — 

 Envelops the spur process of the euro-hyal. 



