352 HEAD AND NECK 



glossus, and is intermixed with the fibres of the chondro- 

 glossus. 



Musculi Longitudinales Inferiores. The inferior longi- 

 tudinal muscles are two rounded, fleshy bundles placed upon 

 the inferior aspect of the tongue, one on each side. Pos- 

 teriorly, each inferior longitudinal muscle lies in the interval 

 between the hyo -glossus and the genio -glossus, and is 

 attached to the hyoid bone ; anteriorly, it is prolonged 

 to the apex of the tongue between the medial border of 

 the stylo-glossus and the genio-glossus ; with the former it is 

 more or less blended. 



Musculus Transversus Lingua. The fibres of the trans- 

 verse muscle lie under the superior longitudinal fibres, and 



M. longitudinalis 



superior ^ 



M. transversus 



M. stylo-glossus 



M. longitudinal!: 

 inferior 



M. hyo-glossus^ 

 M. genio-glossus 



Hyoid bone M. genio-hyoideus 

 FIG. 134. Transverse section through the Tongue. (From Aeby. ) 



constitute a thick layer which extends laterally, from the 

 surface of the septum linguae, to the side of the tongue. The 

 fibres of the genio-glossus ascend through the transverse 

 stratum and break it up into numerous lamellae (Fig. 134). 

 It is joined by the fibres of the glosso-palatinus (Henle) (Fig. 



I 3 2 )- 



Musculus Verticalis Lingua. The vertical fibres extend in 

 a curved direction from the dorsum to the inferior aspect of 

 the tongue, and decussate with the fibres of the transverse 

 muscle. 



Nerves and Vessels of the Tongue. The nerves of the 

 tongue are (i) the glosso-pharyngeal ; (2) the lingual; (3) 

 the hypoglossal; and (4) a few twigs from the internal 

 laryngeal. They should be traced on the left side of the 

 tongue, where the mucous membrane is still in position. 



The glosso-pharyngeal nerve has been traced up to the point 



