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 thB 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 

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



Fig. 70. 

 Muscles of tuf he<*d-Un lateral view, a, Abducens ; 6 c d, Scuto-auriculaxis 

 externus, inferior, ^id-^Te, svBd superior portions ; e, Levator palpebrae superioris 

 extemus; / /, O.bicuiaris palpebrarum;; g, Nasalia longus ; h. Depressor labil 

 inferioris'; i, Buccinc^tor ; ;:, Masseter ; I, Dilatator naris lateralis ; m, Dilatator 

 naris inferior!? ; n. Dilatator na^is superioris. 



DILATATOU iJ rJ.-clS LATERALIS. 



(Pyramidalis — Superr^uxillo-nasalis Magnus. ) 



(PL. II. 7. no. 70. 1.) 



This muscle is situated on the side of the cheek, between the 

 branches of the levator labii superioris, extending horizontally ; it 

 has a flat belly and tendon of origin. 



Attachments. — It 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. 



