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fece of the heart. It gives off five large branches chiefly to 

 the right ventricle ; the laft of thefe, which is the longell, 

 anadomofes near the apex of the heart with the left coronary- 

 artery. 



The left coronary artery is found between the pulmonary 

 artery, and the left auricle. It divides into two branches. 

 The anterior branch takes a Terpentine courfe along the con- 

 vex furfacc of the heart, in the direction of the leptiim ven- 

 triculorum ; it communicates at the apex with the right co- 

 ronary. The pofterior branch paiTes between the left auri- 

 cle and ventricle towards the left margin of the heart, and is 

 diftributcd to the left ventricle. 



GhfefuaUon. Both the coronary arteries fend branches to 

 the roots of the great veflels, as they come off from the 

 heart, and they communicate with the phrenic, internal 

 mammar}', and bronchial arteries. 



The arteria innominata paffes obliquely in front of the 

 trachea, and behind the fubclavian vein. After a courfe of 

 an inch or an ir.ch and a half, daring which it gives off no 

 branch, it divides into the right carotid and right fubclavian 

 arteries : the reft of the defcription of thefe arteries, is the 

 fame on both fides of the body. 



The common carotid artery emerges from the cheft by the 

 fide of the trachea, where it is covered by the infertion of 

 the ilernocleidomaftoideus mufcle. It mounts upwards in 

 front of the vertcbi-se, and parallel with the trachea, till it 

 reaches the upper margin of the thyi'oid cartilage, without 

 giving off a fmgle branch. During its courle along the 

 neck, it is clofely connected to tiie internal jugular vein, and 

 the eighth pair of nerves. At the upper margin of the thy- 

 roid cartilage, it divides into the external and internal caro- 

 tid arteries, the former of which is diftributed to the outfide 

 of the head, the latter to the brain. 



The external carotid continues its courfe upwards between 

 the ramus of the jaw and the ear, being imbedded in the 

 fubftance of the parotid gland. About the middle of the 

 ramus of the jaw, it divides into the fuperficial temporal, and 

 the internal maxillary arteries. 



77'f Branches of the External Carotid Artery, 



The fuperior thyroideal is the firft branch of the external 

 carotid artery-. It purfues a tortuous courfe downwards 

 and forwards to the upper part of the thyroid gland, to 

 which it is almoft entirely diftributed, communicating freely 

 with the thyroid branch of the inferior thyroiJeal artery. 

 It fends however a fuperficial branch under the os hyoides, 

 which unites with its fellow of the oppofite fide. Another 

 branch goes to the lower part ot the thyroid cartilage, and 

 is diftributed to the neighbouring mufcles. The laryngeal 

 artery is the moftconftant brancli of the fuperior tluroideal ; 

 it enters the larynx between the thyroid and cricoid cartila- 

 ges, together with the recurrent nerve, or at a hole in the fide 

 of the thyroid sartilage, and is diftributed to the mufcles of 

 the arytenoid cartilages, and to the membrane which lines 

 the lan'nx. 



The lingual artery comes off from the external carotid 

 immediately above the former ; it accompanies the lingual 

 nerve, palTing above the corner of the os hyoides, and within 

 the hyoglollus mufcle ; it gives a branch (the ramus hyoi- 

 d-eus of authors) to the muleles above the os hyoides ; then 

 it fends a pretty large artery (dorfalis lingure) to the back 

 of the tongue, epiglottis, 5:c. Afterwards the tnnik di- 

 vides into two branches : the fublingual, which paifes be- 

 tween the fublingual gland and the geniohyoidcus mufcle to 

 the chin, where it terminates fuperficially ; and the raninal, 

 which is the larger and more important branch : it continues 

 its courfe along the inferior furface of the tongue, preferv- 

 ing a confiderable iize to the very apex. 



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The labial arter)', which is alfo called the facial, exter- 

 nal maxillary, or angular artery, arifcs from the external 

 carotid under the digaftric and ftylohyoideus mufcles ; it 

 advances in a tortuous manner to the balls of the jaw, palT- 

 ing through a deep fiffure which is made for it in the fub- 

 maxillary gland ; by a bold and fudden turn it bends over 

 the bafis of the jaw at the anterior margin of the mafl'eter 

 mufcle, and then follows a ferpentine courfe over the cheek 

 to the fide of the mouth and nofe, under the zygomatic 

 mufcles. 



Before it paffes over the jaw, it fends off the following 

 branches, i. The afcending palatine artery, goes under 

 the ftyloid mufcles to the pharynx, Euftarhian tube, foft 

 palate, and uvula. 2. An artery to the back of the tongue 

 and tonfils. 3. A number of fmall branches to the fub- 

 maxillary gland, the neighbouring lymphatic glands, the 

 flcin, the membrane of the mouth, &c. 4. The fubmental 

 comes off juft before the artery makes its turn ; it runs 

 forward on the mylohyoideus mufcle towards the chin ; 

 there it turns over the fymphyfis of the jaw, and is diftri- 

 buted to the fliin and mufcles of the chin, communicatinz 

 with the inferior labial arterv. 



When the aitery has paffed over the bafis of the jaw, it 

 fends off; i. A branch to the furface of the maffeter, 

 which communicates with the maffcteric branch of the 

 temporal. 2. The inferior labial artery, which fupplies the 

 lower part of the lower lip, and communicates with the 

 fubmental, and with the coronaiy artery of the lower lip. 

 3. The coronai-y artery of the lower lip, which purfues a 

 winding courfe under the orbicularis oris, till it meets and 

 inofculates with its fellow of the oppofite fide. It is fome- 

 times produced by the inferior labial. 4. The coronary 

 artery of the upper lip may from its fuperior magnitude be 

 confidcred as the continuation of the trunk ; it follows the 

 edge of the upper hp, lying on the membrane of the mouth, 

 and in the middle of tlie lip has a large and free communi- 

 cation with the oppofite artery ; it fends off a large branch 

 to the fide of the nofe, and two fmaUer branches which run 

 along the front of the feptum nafi ; thefe communicate on 

 the ala nafi with the branches of the ophthalmic and infra- 

 orbitary arteries. The branches which the labial fends off 

 to the face vary much in fize and number ; fometimes it 

 terminates in producing the coronary of the lower lip (vide 

 Halleri Icon. fafc. ii. tab. arter. faciei) ; fometimes the na- 

 fal arteries are entirely given off from the ophthalmic ; fome- 

 times the nafal branches of the labial extend over the nofe 

 to the foiehead ; fometimes the branches of one fide differ 

 from thofe of the other. 



The afcending pharyngeal arteiy of Haller (Halleri Icon. 

 fafcic ii. tab. arter. pharyng.), which is the fmalleft branch 

 of the external carotid except the pofterior auricular, either 

 arifes from the back of the carotid oppofite the lingual, or 

 from the point of bifurcation. Its courfe along the neck is 

 ftraight ; it is found in front of the reclus capitis major, 

 and on the fide of the pharynx, being abfolutcly hidden by 

 the two carotids. Its anterior branches fupply the bag of 

 th^ pharynx ; its pofterior branches go to tlie fuperior cer- 

 vical ganglion of the great fympathetic nerve, to the par 

 vagum, and fternomaftoideus mufcle : the termination of 

 the trunk enters the (liuU at the foramen JLigulare, and ra- 

 mifies on the dura mater. The occipital artei-v is covered 

 at its origin by the digaftric mufcle ; it paffes in front of 

 the jugular vein, then gets between the malloid prccefs and 

 the atlas, under the mufcles of the neck. Arriving near 

 the ligamentum nuchse, it penetrates the complexus mufcle, 

 and becomes cutaneous. It fends off brandies to the muf- 

 cle* along which it paffes, one of which is much larger 

 B 2 titan 



