ELEMENTARY EXPERIMENTAL PHYSIOLOGY 



211 



internal border of the jaw bone. The internal border of the digastric 

 muscle is thus exposed. This is pulled aside by a hook so as to expose 

 the transverse fibres of the mylohyoid muscles. 



The mylohyoid is carefully severed following the line of the digastric 

 muscle. The submaxillary and sublingual ducts crossed by the lingual 

 nerve are now exposed in the depth of the wound. Wharton's duct is 

 the larger and external to the sublingual duct. Just where the lingual 

 nerve crosses the ducts it gives off a small branch the chorda 

 tympani. In the angle formed by the origin of the chorda tympani 

 from the lingual nerve there lies the sublingual ganglion (it is erroneous 



m ass 



c/, 



9- 



H yp M.JL 



FIG. 200. Dissection of the submaxillary (G.s.max) and sublingual glands and ducts 

 and the lingual nerve L. The chorda tympani leaves the lingual and runs along the 

 ducts. J.ext, external jugular vein ; V.G, branch of vein to gland ; Hyp, hypoglossal 

 nerve ; M.h., mylohyoid ; dig., digastric ; mass., masseter muscle. (Bernard). 



to term this ganglion " submaxillary "). A ligature is placed beneath 

 the lingual nerve, central to the origin of the chorda tympani, and the 

 lingual nerve is divided central to the ligature. Two ligatures are 

 passed under Wharton's duct, and one is tied. The chorda tympani is 

 then tetanised and the duct filled with saliva. A V-shaped slit is 

 then made into the duct, and a fine glass or silver cannula inserted 

 and tied in. 



The sympathetic fibres run into the gland with the arteries. To 

 expose these the digastric muscle is divided close to its insertion on the 

 jaw bone, and the posterior end of the muscle hooked back. A triangu- 

 lar cavity is thus exposed. The carotid artery with the nerves lie in 

 the lower part of this, while Wharton's canal and the artery of the 

 gland appear in the upper part. The gland itself lies a little more 

 to the back. 



