STYLO-GLOSSUS 



453 



3. STYLO-GLOSSUS 



The stylo-glossus — named from its attachments to the styloid process and 

 tongue (y/.u)(jiTa) — is a long, triangular sheet. 



Origin. — (1) The front of the lower part and tip of the styloid i)rocess of the 

 temi)oral i)one; (2) the upper part of the stylo-mandibular ligament. 



Insertion. — The submucous tissue and subjacent muscular strata of the side of 

 the t(jngue and the adjacent parts of its under surface. 



Structure. — Arising by short tendinous fibres, the muscle soon develops into a 

 long, fan-shaped, laterally-compressed sheet, which passes in a long curve, with an 

 upward concavity, forwards and slightly downwards and inwards to the side of the 

 tongue, where it partly overlaps and partly interlaces with the hyo-glossus muscle, 

 forming with this nuiscle and some of the fibres of the palato-glossus a thin super- 

 ficial stratum which is continued forwards to the tip of the tongue. 



Nerve-supply. — From the hypoglossal nerve, by filaments which enter its ex- 

 ternal surface. 



Fig. 315. — Su)E View of the Muscles of the Tongue. 



Lingualis inferior 



Qenio-hyo-glossus — 



Genio-hyoid 

 Anterior belly of 

 digastric 



Hyo-glossus 



Mylo-hyoid 



Action. — (1) To draw back the tongue — for this purpose it arises from the 

 styloid process as low as possible and below the level at which the two other styloid 

 muscles arise; (2) to draw upwards the sides of the tongue, so as to help the genio- 

 hyo-glossi and some of the intrinsic muscles in making its upper surface concave 

 from side to side. 



Relations. — Superficially, the internal pterygoid, tlie parotid gland, lingual 

 gustatory nerve, and the mucous membrane of the side of the tongue; deei)ly, the 

 stylo-pharyngeus, hyo-glossus, inferior lingualis and genio-hyo-glossus, with tlie 

 glosso-pharyngeal nerve. 



4. PALATO-GLOSSUS 



The palato-glossus — named from its attachment to the soft palate and tongue 

 (y?.u)(T(Ta) — is a somewhat cylindrical muscle which expands at either end into a 

 thin sheet. 



Origin. — The under surface of the aponeurosis of the soft palate; and at the 

 middle line its fibres are continuous with those of its fellow of the opposite side. 



