200 CIRCULATORY SYSTEM. 



from the laryngeal branch, or from the thyroid artery itself, is 

 spent upon the crico-thyroid muscle, and traversing the front 

 surface of the middle crico-thyroid ligament, anastomoses with 

 its fellow : small twigs from this branch penetrate to the interior 

 of the larynx through the middle crico-thyroid ligament. Some- 

 times this crico-thyroid ramus is superior in size to the one 

 above, in which case it principally supplies the interior of the 

 larynx. 



The Thyroid Branch is the continuation of the principal 

 trunk; it penetrates into the substance of the thyroid gland, and 

 divides into two ramuscles, one of which goes along the poste- 

 rior face of the lobe of the gland, and anastomoses with the in- 

 ferior thyroid; the other goes along the upper margin of the 

 gland, and anastomoses with its congener of the opposite side. 

 The thyroidal artery is split up into a great many branches in 

 the substance of the gland, it also sends small branches to 

 the pharynx, oesophagus, and the little muscles on the front of 

 the neck. 



The Lingual Artery (Art. Lwgualis) comes from the external 

 carotid at the distance of from six to twelve lines above the su- 

 perior thyroid, and goes to the tongue. It is concealed in the 

 early part of its course by the digastric and the stylo-hyoid mus- 

 cles; it then penetrates the hyo-glossus muscle just above the 

 cornu of the os hyoides, or goes between it and the middle con- 

 strictor of the pharynx ; it then ascends between the hyo-glossus 

 and the genio-hyo-glossus muscle; advancing forwards, it is 

 placed between the latter and the sublingual gland, and, finally, 

 reaches the tip of the tongue. 



The lingual artery sends off the following branches. At the 

 root of the tongue one or more trunks arise from it (Dorsales 

 Linguce) which go to the base of this organ, the tonsils, the pa- 

 late, and the epiglottis. A little farther on, this artery detaches 

 another branch, (Ramus Sublingualis,) which, advancing be- 

 tween the mylo-hyoid and the genio-hyo-glossus muscles, and 

 above the sublingual gland, detaches a great many ramifications 

 to these parts and to the lining membrane of the mouth; it is 

 sometimes a branch of the facial. The Ramus Raninus, is the 

 continuation of the lingual; it advances between the lingualis 

 the genio-hyo-glossus muscle, to the tip of the tongue, distri- 



