ORGANS OF PREHENSION. 223 



which, constitute the mouth. The mouth contains the den- 

 tal organs, and has its superior wall or roof formed by the 

 palatine processes of the superior maxillary and palate bones. 

 Its floor consists of the mylo-hyoid muscles. The lips bound 

 it in front, the soft palate behind, and the cheeks laterally. 



SECTION I. 



ORGANS OF PREHENSION, 



WHICH CONSIST OF THE MUSCLES OF THE MOUTH. 



Dissection. To expose the muscles of prehension, com- 

 mence the first incision at the meatus externus of the ear, 

 carrying it along the zygoma to the external canthus of 

 the eye; thence round the lower margin of the orbit to the 

 inner canthus, and up to the nasal spine of the os-frontis; 

 from this continue the incision along the median line of 

 the nose to its tip, thence down to the margin of the upper 

 lip; from this continue round the margin and angle of the 

 mouth to the middle of the lower 



FIG. 55. 



lip; thence down to the lower 

 margin of the chin; and thence 

 along the sides and up the rami 

 of the lower jaw, back to the 

 place of beginning. Make a sec- 

 ond incision from the promi- 

 nence of the malar bone to the 

 angle of the mouth. Turn the' 

 integuments from the ear to- 

 wards the mouth. Hold the 

 skin tense, and always dissect 

 in the course of, and close to, 

 the fibres of the muscle. The 



FIG. 55 represents a front view of the Muscles of the Face, a a Anterior 

 bellies of the occipito-frontalis. 6 6 Orbicularis palpebrarum. c Fyramidales 

 nasi. d Compressor nasi. e e ff Levator labii-superioris-alaeque 'nasi. g g 

 Zygomaticus minor, hh Zygomaticus major, ti Masseter. jj Buccinator 

 or trumpeter's muscle, k k Orbicularis oris. 1 1 Depressor-labii-inferioris. 

 m Levator menti. n n Depressor-anguli oris. o o Levator-anguli-oris. 



