THE SALIVARY GLANDS. 



437 



Excretory/ canal. — Wharton'' s duct, as it is termed, is long and narrow ; has 

 very attenuated walls, and exists for nearly the whole length of the superior 

 border of the gland (sometimes on its internal face), where it receives the 

 ramifications from various lobules. At the anterior extremity of the organ it is 

 free, and passes forward between the mylo-hyoideus and hyo-glossus muscles. 

 After crossing, outwardly, the glosso-facial artery and great hypoglossal nerve, 

 and, inwardly, the tendon of the digastricus and the lingual nerve, it passes 

 between the great hyo-glossus muscle and the sublingual gland, lying closely to 

 the inner side of the latter ; thus it extends parallel to the lateral groove (or 

 channel) of the lingual canal on the floor of the mouth. It finally arrives near 



Fig. 248. 



MAXILLARY AND SUBLINGUAL GLANDS. 



R, Maxillary gland ; S, Wharton's duct ; T, sublingual gland. 



the frfenum of the tongue, but underneath the buccal membrane, and opens into 

 the mouth by a small, but very salient, floating tubercle, situated a httle in 

 advance of the frsenum, and vulgarly named the iarb {harhillon). 



The structure of Wharton's duct is identical with that of Steno, but its 

 external tunic is extremely thin, and has not any circular elastic fibres. 



3. Sublingual Gland (Fig. 248). 



This is less in volume than the preceding, and is situated under the tongue, 

 in the submaxillary space. 



Elongated from before to behind, and very flat laterally, it has, like the 



