MUSCLES OF NOSE. 



35 



which joins that of the compressor naris. Along its inner border is the 

 muscle of the opposite side. 



Action. This muscle makes tight the skin over the nasal cartilages, 

 but renders lax, and sometimes wrinkles transversely the skin towards the 

 root of the nose. 



CoMi'KKssoii NARIS. This muscle (fig. 5, 3 ) is not well seen till after 

 the examination of the following one. Triangular in shape, it arises by 

 its apex from the canine fossa of the upper maxillary bone. The fibres 

 are directed inwards, spreading out at the same time, and end in an 

 aponeurosis, which covers the cartilaginous part of the nose, and joins the 

 tendon of the opposite muscle. This muscle is partly concealed by the 

 next the common elevator of the ala of the nose and the upper lip. 



Action. It stretches the skin over the cartilaginous part of the nose. 



The LEVATOR LABII SUPERIORIS Ai^EQUE NASI (fig. 5, 2 ) is placed by 

 the side of the nose, and arises from the top of the nasal process of the 

 upper maxillary bone, internal to the attachment of the orbicularis. As 

 the fibres descend from the inner part of the orbit the most internal are 



Fig. 5. 



1. Pyramidalis iiasi. 



2. Common elevator of the nose and lip. 



3. Compressor naris. 



4 and 5. The two slips of the dilatator naiis. 



6. Depressor ale nasi. 



7. Orbicularis oris, attached to the septum nasi. 



MUSCLES OF THE NOSE. 



attached by a narrow slip to the wing of the nose, whilst the rest are 

 blended interiorly with the orbicularis oris. Near its origin the muscle is 

 partly concealed by the orbicularis palpebrarum, but in the rest of its 

 extent it is subcutaneous. Its outer border joins the elevator of the 

 upper lip. 



Action. As the name expresses, it can raise the upper lip, and draw 

 outwards the wing of the nose, dilating the aperture ; but when the mouth 

 is shut it can enlarge the nostril independently of the lip. 



Dilatator Naris. In the dense tissue on the outer side of the nostril 

 are a few muscular fibres, both at the fore and back part of that aperture 

 (fig. 5, 4 , and 6 ), to which the above name has been given by Theile: they 

 are seldom visible without a lens. The anterior slip, *, | asses from the 

 cartilage of the aperture to the integument of the margin of the nostril ; 

 and the posterior, 5 , arising from the upper jawbone and the small sesa- 

 moid cartilages, ends also in the integuments of the nostril. 



