194 HEAD AND NECK 



gain insertion into the anterior aspect of the body of the 

 hyoid bone. It is supplied by the hypoglossal nerve. It pulls 

 the hyoid bone upwards and forwards. 



The Deep Part of the Submaxillary Gland. It has been 

 noted already that the small, deep part of the submaxillary 

 gland springs from the medial surface of the superficial part, at 

 the posterior border of the mylo-hyoid muscle. It will now be 

 obvious that it passes forwards and upwards, between the 

 mylo-hyoid laterally and the hyo-glossus and genio-glossus 

 medially, until it comes into contact with the sublingual gland. 

 It is accompanied by the lingual nerve and the submaxillary 

 duct, both of which lie on its medial surface (Fig. 72). 



Ductus Submaxillaris. The duct of the submaxillary 

 gland (O.T. Wharton's duct) emerges from the medial surface 

 of the main part of the gland, and proceeds, with the deep 

 part of the gland, forwards and upwards upon the hyo- 

 glossus muscle. At first it lies between the lingual nerve 

 above and the hypoglossal nerve below. Reaching the 

 surface of the genio-glossus muscle, it is crossed laterally, 

 and then below and medially, by the lingual nerve. Then it 

 passes to the medial side of the sublingual gland, and gains the 

 floor of the mouth, where it opens by a small orifice placed 

 on the summit of a papilla which lies close to the side of the 

 frenulum linguae. 



The wall of the duct is much thinner than that of 

 the parotid duct. If a small opening is made in it, the 

 dissector will experience little difficulty in passing a fine probe 

 or bristle along it into the mouth. 



Glandula Sublingualis. The sublingual gland lies in the 

 floor of the mouth, and is the smallest of the larger salivary 

 glands. It is almond-shaped, about one inch and a half 

 long ; and its relations are very definite. Its prominent upper 

 border can be seen within the mouth, beneath the anterior 

 part of the tongue, where it is covered by a fold of mucous 

 membrane termed the plica sublingualis (Fig. 105). Medially^ 

 it rests upon the genio-glossus, musr!^ _wj~pfc^ laterally, it lies 

 against the medial aspect of the body of the mandible, 

 immediately lateral to the symphysis and above the mylo- 

 hyoid line. Below^ it is supported by the mylo - hyoiH 

 muscle. Its anterior extremity reaches the median plane, 

 above the anterior border of the genio-glossus, and is in 

 contact with its fellow of the opposite side. The duct of 



