NASAL MUSCLES. 



165 



Origin. — It arises from the surface of the superior maxilla, at 

 its junction with the malar and lachrymal bones. 



Insertion. — The tendon passes to the extremity of the nose, 

 where, joining its fellow, it forms a radiating expansion, becoming 

 lost in the upper lip. 



Action. — It elevates and corrugates the upper lip, if acting 

 vwith its fellow ; if acting alone, it pulls the lip to one side. 



Fio. 70. 



Musdes of tiie hejid-- left lateral view, a, Abdacens ; 6 c d, Scuto-auricularis 

 extemus, inferior, iiiiddie, Mid superior portions ; e. Levator palpebrae superioris 

 externns ; / /, 0»bicu?aris paljienrarum ;'i g, Nasaiis longus ; h. Depressor labii 

 inferioris ; i. Buccinator : Ic, X^as^eter ; I, DHatator naris lateralis ; m. Dilatator 

 naris inferioris ; n, Dilatato.' naxis juperioris. 



DILATATOIl 



itlS LATERALIS. 



(Pyramidalia — Superrh^xillo-nasalis Magnus.) 

 (Pl. n. 7. rxa. 70. 1.) 



This muscle is situated on the f^ide of the cheek, between the 

 branches of the levator labii superioris, extending horizontally ; it 

 has a flat belly and tendon of origin. 



Attachments. ~lt arises from the anterior extremity of the 

 maxillary spine ; it is inserted to the side of the nostril and the 

 upper lip, blending with the orbicularis oris. 



Action. — It dilates the nostril, acting on its external wing. 



