484 



THE ARTERIES 



platysnia, and deep fascia. Here it lies on the middle constrictor muscle and 

 superior laryngeal nerve. After ascending a short distance, it curves downwards 

 and forwards beneath the hypoglossal nerve, and, in the second part of its 

 course, runs horizontally along the upper border of the hyoid bone, beneath the 

 hyo-glossus, l)y which it is separated from the hypoglossal nerve, the posterior 

 belly of the digastricus and the stylo-hyoid muscles, and the lingual vein. In this 

 part of its course it lies successively on the middle constrictor of the pharynx and 

 the genio-hyo-glossus muscle, and crosses a small triangular space known as 

 ' Lesser' s triangle,' the sides of which are formed by the tendons of the digastric, 

 the base by the hypoglossal nerve, and the floor by the hyo-glossus muscle, in 

 which situation it is usually tied. In the third part of its course it ascends 

 tortuously, usually beneath the anterior margin of the hyo-glossus, to the under 

 surface of the tongue, and is thence continued to the tip of that structure h'ing 

 between the lingualis and the genio-hyo-glossus muscles. From the anterior edge 

 of the hyo-glossus to its termination, it is only covered by the mucous memlirane 

 of the under surface of the tongue. This part of the vessel is sometimes called 

 the ranine artery. 



Fig. 333. — Scheme of the Right Lingual Arteey. (Walsham.) 



Palato-glossus 



Descending palatine arleri, 

 Palato-pharyngeus 



TONSIL 



Ascending palatine branch 



of facial 



Tonsillar branch of dorsalis 



lingiue 



Tonsillar branch of facial 



Stylo-glosBus 



Bursalis lingua; artery 



Middle constrictor 



HYPOGLOSSAL JHERVE 



Facial artery 



Posterior belly of digastric 

 and stylo-hyoid 

 Snpru-hi/'jid branch 



SUP. LARYNGEAL X. 



Infra-hyoid branch 

 Internal carotid artery 



Ranine artery 



Genio-hyo- 

 glossus 



Artery of 

 1'roenUNt 



Hyo-glossus 



Snblingiial 



arter;/ 



Genio-hyoid 

 Anterior belly 



of digastric 

 Subiiienlal 



artery 

 I artery 



Common carotid artery 



Branches of the Lingial Artery 



The named branches of the lingual artery are: — (1) The hyoid: (2) the 

 dorsalis linguae; (o) tlie sulilingual: and (4) the ranine. 



(1) The hyoid, or supra-hyoid (fig. 333), is a small vessel Avhich arises from 

 the first part of the lingual, and courses along the upper border of the hyoid bone, 

 superficial to the hyo-glossus, but beneath the insertion of the posterior belly of the 

 digastricus and stylo-hyoid. It anastomoses with its fellow of the opposite side, 

 and with the infra-hyoid, a branch of the superior thyroid artery, and supplies the 

 contiguous muscles. 



(2) The dorsalis linguae (fig. 333) arises from the second portion of the lingual 

 artery, usually under cover of the posterior edge of the hyo-glossus muscle. It 

 ascends to the back of the dorsum of the tongue, and, dividing into branches, 

 supplies the mucous membrane on each side of the V formed l)y the circumvallate 

 papillae. It also supi:)lies the pillars of the fauces and the tonsil, where it anasto- 

 moses with the other faucial and tonsillar arteries. Instead of a single artery, as 

 above described, there may be several small vessels running directly to the parts 

 mentioned. The artery anastomoses in the mucous membrane by very small 



