THE MUSCLES. 137 



glossus. Or.: Proc. styloideus (apex). Ins.: double in M. 

 lingualis. Use: to draw the tongue upwards and to its own 

 side. Both acting together draw it upwards and backwards, 

 making it appear broad. 



Nerves: hypoglossus. 



194. 2. Hyo-glossus (Basio-, Kerato-, Chondro-glossus}. 

 Pos. : vertical, above M. mylo-hyoideus. Externally : M. 



stylo-gloss., digastricus, Gland, subling., Nn. hypogloss. and 

 lingualis. Internally : Art. lingual., M. geniogloss, constrict, 

 vied. Or.: three-fold from the hyoid bone; 1. from body; 2. 

 from greater; 3. from lesser cornu. Ins.: root of tongue (m. 

 lingualis). Use: to draw the tongue downwards and back- 

 wards ; both acting, draw it down and narrow it. 



195. 4. Genio-glossus [_Genio-hyo-glossus~]. 



Pos. : close above M. genio-hyoideus, horizontal, beneath the 

 oral mucous membrane and the tongue. On the inside both 

 meet together. Outside : Gland, subling., N. hypogl., and the 

 muscles before mentioned. Fig. : thick, three-sided, large. Or. : 

 chin (spina interna). Ins.: tongue. The posterior fibres pass 

 to the hyoid bone, the anterior curved from the root to the apex 

 of the tongue to the m. lingualis. Use : both extend the tongue 

 forwards, draw it again backwards, and press it together to form 

 a furrow. 



Nerves: (three to four) lingual, trigemini, glosso-pharyng. and hypoglossus. 



196. 5. Constrictores pharyngis, three constrictors of the 



pharynx, 



form the posterior, muscular parietes of the pharynx, in the 

 centre of which they meet together in a white line [raphe] formed 

 of fibre-cellular tissue. From behind we first see : 



a. Constrictor pharyngis inferior, the strongest of the three 

 muscles, extending the lowest downwards. Its fibres pass from 

 the raphe downwards, outwards, and forwards, blending imme- 

 diately with those of the esophagus (see Splanchnol.), and 

 reaching above to the constrictor superior. Inferior attachments : 

 1. Cariilago cricoidea (thence, crico-pharyngeus). 2. C. thy- 

 reoidea (M. thyreo-pharyngeus). 3. Lig. hyo-thyreoideum 

 laterals (M. syndesmo-pharyngeus). Superior attachments : 

 raphe. 



b. Constrictor pharyngis medius. Inf. attach.: 1. Cornu 

 maj. oss. hyoidei (thence, M. ccrato-pharyngeus). 2. Cornu 

 minus oss. hyoidei (thence, M. chondro-pharyngeus). Superior 

 attach.: 1. raphe. 2. Oss. occipitis pars basilaris. 



