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Part III. ANA T O M Y. 227 pofteriores; and then the intercoftales from its pofte- divided into two large branches or particular carotids, one rior part, which in fome fubjedls come all from this por- named external, the other internal, becaufe the firft goes tion of the aorta, in others only the lowefl: eight or chiefly to the external parts of the head, the fecond enters the cranium, and is diftributed to the brain. nine. The inferior portion of the defcending aorta, as it paf- The external carotid is anterior, the internal pofterifes through the diaphragm, gives off the diaphragmatica; or ; and the external is even fituated more inward, and inferiores, or phrenicte; afterwards it fends off feveral nearer the larynx, than the other. The external carotid is the fmalleft. It runs infenfibranches, anteriorly, polleriorly, and laterally. The anterior branches are the aeliaca, which fupplies bly outward, between the external angle of the lower the ffomach, liver, fpleen, pancreas, (be. the mefente- jaw, and the parotid gland, which it Supplies as it pafrica fuperior, which goes chiefly to the mefentery, to Jes. Afterwards it afeends on the fore-fide of the ear, the fmall inteftines, and that part of the great i‘ntel tines and ends in the temples. which lies on the right fide of the abdomen ; the me- In this courfe it fends off feveral branches, which may fenterica inferior, which goes to the great inteftines on well enough be divided into anterior or internal, and pothe Jeft fide, and produces the hasmorrhoidalis interna; fterior or external; and the principal branches of each kind are thefe: and laftly, the right and left arteriae fpermaticae. The pofterior branches are the arteriae lumbares, of The firft anterior or internal branch goes out from the .which there are feveral pairs, and the faerse, which do very origin of the carotid on the infide ; and having prenot always come from the trunk of the aorta. fentjy afterward taken a little turn, and fent off branches • The lateral branches are the c'apfulares and adipofe, to the jugular glands near it, to the fat and Ikin, it runs the origin of which often varies; the renales, formerly tranfverfely, and is diftributed to the glandulse thyroitermed emulgents; and the iiiacae, which terminate the dtese, and to the mufcles and other parts of the larynx: It likewife fends fome branches to the pharynx and mufaorta by the bifurcation already mentioned. • The iliac artery on each’ fide is commonly divided into cles of the os hyoides. the external or anterior, and internal or pofterior. The fecond anterior branch paffes over the neareft corThe internal iliaca is likewife named arteria hypoga- nu of the os hyoides, to the mufcles of that bone and ftrica ; and its ramifications are dillributed to the vifeera the tongue, and to the glandulae fublinguales ; afterwards ■ contained in the pelvis, and to the neighbouring parts, palling before the cornu of the os hyoides, it lofes itfelf both internal and external. in the tongue, from whence it has been called arteria The iliaca externa, which is the true continuation of fublingualis. the iliac trunk, goes on to the inguen, and then out of The third branch, or arteria maxillaris inferior, goes the abdomen, under the ligamentum Fallopii; having firft to the maxillary gland, to the ftyloid and maftoid muldetached the epigaftrica, which goes to the mufeuli ab- cles, to the parotid and fublingual glands, to the mufdominis redti. Having quitted the abdomen, it com- cles of the pharynx, and to. the fmall flexors of the mences arteria cruralis, which runs dowm upon the thigh, head. and is diftributed by rqany branches and ramifications to The'fourth branch, arteria maxillaris externa, paffes all the lower extremity. anteriorly on the mafleter mufcle, and middle of the low• We fhall now go on to examine particularly all the ca- er jaw, near the chin. Afterwards it runs under the pital or original branches of the aorta, from their origin, mufculus triangularis labiorum, which it fupplies as well to the entry of them and of their ramifications into all as the buccinator and the quadratus menti. parts of the body. It fends of a particular branch, very much contorted, r The Cardiac or coronary arteries of the heart arife which divides at the angular commiffure of the lips, and from the aorta immediately on its leaving the heart. running in the fame manner along the fuperior and infeThey are two in number, and go out near the two fides portions of the mufculus orbicularis, it communicates of the pulmonary artery, which having firft furrounded, riorboth fides with its fellow, and thereby forms a kind they afterwards run upon the bafis of the heart in form ofon arteria eoronaria labiorum. of a kind of crown, or garland, from whence they are Afterwards it afeends towards the nares, and is diftricalled coronariae; and then purfue the fuperficial traces buted to the mufcles, and other parts of the of the union of the two ventricles, from the bafis of the nofe, fending down fomecartilages, which communicate with heart to the apex, and are afterwards loft in the fubftance the coronary artery of thetwigs lips. Laftly, it reaches the of the heart. great angle of the. eye, and is ramified and loft on the The Carotid arteries are two in number, one called mufculus orbicularis palpebrarum, fupercillaris, and fronthe right carotid, the other the left. They arife near each other, from the curvature of the aorta, the left im- talis. Through all this courfe,. it is named arteria anmediately, the right moft commonly from the trunk of gulaiis. 1 he fifth branch, maxillaris interna, arifes over-againft the fubclavia on the fame fide. condyle of the lower jaw. It paftes behind the con* They run upon each fide of the trachea arteria, be- the dyle, and having given off a twig among the mufeuli tween it and the internal jugular vein, as high as the la- pterygoidasi, it is divided into three principal branches. rynx, without any ramification. Each of fnefe trunks is I he firft branch, or fpiicno-maxillaris, gous through afterwards ramified in the following manner. the inferior orbitary, or fphenomaxillary fiffure, to the The trunk having reached as high as the larynx, is oxbit, alter having fupplied the mufeuli periftaphylini, and