242 Anatomy of the Rabbit. 



mylohyoid nerve. These structures, together with the 

 inferior alveolar artery may be freed from their loose 

 connections with the pterygoidei, 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 ventral surface of the neck as follows: 



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

 given off from the dorsal wall (pp. 133, 278). 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. The tendon of the digastricus 

 may be reflected. 



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

 wall and passes forward into the tongue. 



The hypoglossal nerve crosses the ventral surface of the artery 

 and should be kept intact. 



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

 given off immediately in front of the lingual artery, some- 

 times in common with it. It passes forward on the medial 

 surface of the ventral border of the mandible (medial to the 

 digastricus), giving branches to the submaxillary gland and 

 to the muscles of mastication. The vessel has been divided 

 at the point where it passes aroung 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. 251), giving off the inferior 

 alveolar artery to the mandible. 



(f) The superficial temporal artery (a. temporalis super- 

 ficialis), 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. 



