218 LABORATORY MANUAL OF HUMAN ANATOMY 



(a) Lymph-glands. 



(aa) Submaxillary lymph-glands (lymphoglandulae submaxil- 



lares). There are three, anterior, middle, and posterior. 



(ab) Submental lymph-glands (between the anterior bellies of Mm. 



digastrici of the two sides). 



In cancer of the lip which glands are likely to be the 

 seat of metastatic growth? 



(b) Submaxillary salivary gland (glandula submaxillaris) . 



Study also the following : 



Arteries. 



(a) External maxillary artery (A. maxillaris externa) (0. T. facial 



artery). 



(aa) Ascending palatine (A. palatina ascendens). 



(ab) Tonsillar ramus (ramus tonsillaris). 



(ac) Submental (A. submentalis). 



(ad) Glandular rami (rami glandular es) . 



(b) Mylohyoid ramus of internal maxillary artery (ramus mylohyoideus 



A. maxillaris internae). 



(c) Lingual artery (A. lingualis). This is really not in the triangle, 



being beneath its floor, as it is completely covered by the M. 

 hyoglossus. It is very important to study it, however, in this 

 situation, as it is the point where it is ligated. Notice that it lies 

 in a minute triangle (Lessees triangle), formed by the margin 

 of the M. mylohyoideus, the venter posterior M. digastrici, and 

 the N. hypoglossus. If the M. hyoglossus be exposed within this 

 little triangle and the muscle split vertically, the lingual artery is 

 exposed. (Fig. 113.) 



Veins. (Vide Fig. 87, p. 206.) 



(a) Anterior facial vein (V. facialis anterior) and tributaries. 



(aa) Submental vein (V. submentalis). 



(ab) Palatine vein (V. palatina). 



(b) Tributaries of internal jugular vein (V. jugularis interna). 



(ba) Lingual vein (V. lingualis). 



(bb) Vein accompanying hypoglossal nerve (V. comitans N. 



hypoglossi). 

 Nerves. 



(a) Hypoglossal nerve (N. hypoglossus). 



(b) Mylohyoid nerve (N. mylohyoideus) from the third division of 



the fifth cerebral nerve. 



In the posterior portion of the triangle find 



(a) Lower part of parotid gland (glandula parotis). 



(b) External carotid artery (A. carotis externa). 



(ba) Posterior auricular artery (A. auricularis posterior). 



Carotid Triangle. (Vide Fig. 91.) 



Why is it so called! Find in it and study the following 

 structures : 



