162 Anatomy of the Rabbit. 



The corresponding inferior alveolar vein leaves the mandible 

 at this point, 

 (f) The inferior alveolar nerve (n. alveolaris inferior) accom- 

 panies the inferior alveolar artery to the mandible. The con- 

 tinuation of the nerve is the mental nerve. It appears at the 

 mental foramen, and passes to the lower lip. 

 The origin of the inferior alveolar nerve may be traced. It 

 arises from the mandibular nerve (n. mandibularis), the third 

 division of the fifth cranial or trigeminal nerve (n. trige- 

 minus), which also gives off anteriorly the stout lingual nerve 

 to the tongue and posteriorly the slender mylohyoid nerve. 

 These structures, together with the inferior alveolar artery, 

 may be freed from their loose connections with the ptery- 

 goids, so that they may be left in place for further study. 

 The two pterygoidei may then be detached at their point of 

 origin from the skull and removed. 



6. The branches of the common carotid may be traced in the anterior 

 portion of the neck as follows : 



(a) The internal carotid (a. carotis interna) is a small vessel given 

 off from the dorsal wall (pp. 171, 190). The trunk then 

 passes forward as the external carotid (a. carotis externa). 



(b) The occipital artery (a. occipitalis) passes from the dorsal wall 

 to the posterior portion of the head. 



The stylohyoideus major, a slender muscle arising with the digastricus • 

 from the stylohyoid ligament and inserted on the greater cornu of 

 the hyoid, should be divided. 



(c) The lingual artery (a. lingualis) arises from the ventral wall 

 and passes forward into the tongue. 



(d) The external maxillary artery (a. maxillaris externa) is given 

 off immediately in front of the lingual artery, sometimes in 

 common with it. It passes forward on the medial surface 

 of the ventral border of the mandible (medial to the digas- 

 tricus), giving branches to the submaxillary gland and to the 

 muscles of mastication. The vessel has been divided at the 

 point where it passes around the ventral border of the 

 mandible to the lateral surface of the face. 



(e) The internal maxillary artery (a. maxillaris interna), one of 

 the two terminal branches of the external carotid, passes in 

 the direction of the orbit (p. 168), giving off the inferior 

 alveolar artery to the mandible. 



(f) The superficial temporal artery (a. temporalis superficialis), 

 the second terminal branch, passes dorsad to the temporal 

 region, supplying the latter and the base of the ear. The 

 transverse facial artery, which crosses the cheek, is an anterior 

 branch of this vessel. 



7. Dissection of the tongue and hyoid : 



(a) The stylohyoideus major muscle. Origin: Jugular process 



