THE TONGUE 



nil 



the superior and inferior longitudinal muscles. The fibres arise from, or pass through, the sep- 

 tum linguse, and are attached to the mucosa of the dorsum and lateral margins of the tongue. 

 The verticalis linguae (fig. 861) is composed of fibres which pass from the mucosa of the dorsum 

 to the mucosa of the inferior surface of the tongue, interlacing 'with those of the other intrinsic 

 and extrinsic muscles. 



Fig. 



861. — Transverse Section through the Left Half of the Tongue. (Magnified.) 

 (From a preparation by Mr. J. Pollard, Middlesex Hospital Museum.) 



Transversus linguae 



Mucosa of dorsum 



Longitudinalis 

 superior muscle 



Septum 



Longitudinalis infe- 

 rior (mixed with 

 extrinsic fibres) 



Lateral margin of 

 tongue 



Verticalis linguae 



Vessels and nerves. — The lingual arteries furnish the principal blood-supply. The lingual 

 veins carry the blood from the tongue to the internal jugular. The lymphatics form a network 

 in the lamina propria, connected with a deeper network in the submucosa. The latter forms 

 plexuses around the lingual follicles. The efferent lymph-vessels from the tongue empty chiefly 

 into the superior deep cervical lymph-nodes. (For details concerning the blood- and lymph- 

 vessels, see Sections V and VI.) The nerves are motor and sensory. The hypoglossal nerve 



Fig. 862. — Schematic Representation of the Distribution of tee Sensory Nerves 

 in'the Mucous Membrane of the Tongue. (Areas of distribution according to R. Zander. 

 White dotted area indicates vagus; oblique lines, glosso-pharyngeal; horizontal lines lingua 

 nerves.) 



Right vagus nerve 



Right glosso- 

 pharyngeal 

 nerve 



Left vagus nerve 



Left glosso-phar- 

 yngeal nerve 



Right lingual nerve 



Left lingual nerve 



supplies the intrinsic and all the extrinsic muscles of the tongue except the glossopalatinus 

 (palato-glossus), which is supplied from the pharyngeal plexus. The sensory nerves (fig. 862) 

 are: — the lingual nerve, a branch of the mandibular division of the fifth, which, after joining with 

 the'chorda tympani from the seventh, is distributed to the anterior two-thirds of the tongue and 

 represents the nerve of touch; the lingual branches of the glossopharyngeal, w^hich are distrib- 



