136 SPECIAL ANATOMY. 



bone obliquely backwards and upwards; elevates the root of the 

 tongue, and contracts the isthm.faucium. 



Nerves : fadalis. 



190. 9. Mylo-hyoideus (s. transversus mandibulse). 



Pos. : extended like a partition from the lower jaw to the hyoid 

 bone; above M. digastric, (ant. belly) and Gland, submaxil- 

 lar.; beneath Mm. genio-hyoid., hyo-, stylo- glossus, Nn. lin- 

 gualis and hypo-glossus, Gland, subling. arid oral mucous memb. 

 Or.: broad from the entire Lin. obliq. interna of the lower jaw. 

 Ins. : pointed to the centre of the body of the hyoid bone, 

 f Meets its fellow in the middle line of the body.] Use : draws 

 the hyoid bone upwards, or the lower jaw downwards. 



Nerves: trigeminus. 



191. 10. Genio-hyoideus. 



Pos. : above the last m., beneath m. genio-glossus, between 

 chin and hyoid bone, below and behind. Or. : the chin (spina 

 mentalis interna). Ins. : Hyoid bone (the superior anterior part 

 of the centre). Use : draws the hyoid bone forwards and upwards, 

 or the lower jaw downwards. 



Nerves : hypoglossus. 



B. Muscles of the Tongue, of the Pharynx, and Palate. 



192. 1. Linguales, Tongue muscle. 



a. Longitudinalis superior, anteriorly beneath the thick mem- 

 brane of the tongue, behind beneath the glandular layer, along 

 the entire dorsum of the tongue. Use: to shorten the tongue, 

 curving the apex upwards and backwards. 



b. Longitudinalis inferior (especially the lingualis), spindle- 

 shaped on the under surface close to the middle line, between 

 genio- and hyo-glossi. Use: to shorten the tongue, curving the 

 point downwards. 



2. Transversus, springs from the fibrous septum in the centre 

 of the tongue; its fibres cross each other; lies between the two 

 longitudinales. Use: to narrow, elongate, and point the tongue. 



193. 2. Stylo-glossus. 



Pos. : obliquely inwards, downwards, and forwards, partly on 

 the borders, partly transverse in the tongue. Externally lie: M. 

 stylo-hyoideus, Parotis, M. pterygoid. intern., Gland, sublin- 

 gual, N. lingualis, mucous membrane of the tongue. Internally : 

 Lig. stylo-hyoid., Tonsilla, M. constrictor pharyng. super., hyo- 



