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 O M Y. 239 PartIV. A N A 1 the right ribs, together with the artery of the fame name. and face, running up toward the angle'of the lower jaw, the pofterior goes to the temples and occiput. Having reached near the diaphragm, it fends it a branch andThe-anterior external jugular vein is often a branch of which runs toward the tendinous plane, and communithe jugularis interna, and fometimes it comes from the cates with the common diaphragmatic veins. Afterwards this mammary vein gives fmall branches to vena axillaris. the mediaftinum, and others between the ribs to the in- It runs up toward the lateral part of the lower jaw, teguments ; of which thofe that pafs between and under between the angle and the chin, and fends feveral branches backwards, and inwards. the cartilages of the laft true ribs, run down on the in- forwards, ner or pofterior fide of the mufculi re6H abdominis, be- Pofteriorly it gives, (i.) A large branch on the fide of ing ramified among their flelhy fibres, and communica- the upper part of the larynx, which communicates with the jugularis interna, and likewife with a large-fhort ting with the epigaftric veins by feveral fmall twigs. branch'of the jugularis externa pofterior. (2.) A fmall The left internal mammaria arifes anteriorly from the left fubclavian, oppofite to the cartilage or anterior ex- branch, which has the fame communication, but which is not always to be found. (3.) Another fniall branch a tremity of the firfl true rib. The right vena thymica, when it arifes feparately, little below the lower jaw, which commuqicates with the goes out from the bifurcation ; and when it is wanting, jugularis externa pofterior. the thymus, from ,whence it takes its name, is furnilhed Anteriorly it fends feveral branches to the mufcles of by the gutturalis, or fome other neighbouring vein. the larynx, fterno-hyoidtei, thyro-hyoidae, and to the inThis vein often reaches no lower than the inferior part teguments ; and below the larynx it fends communicaof the thymus; $nd the left vein of the fame name ting branches to the jugularis externa anterior of the’ocomes from the left fubclavian, almoft oppofite to the ther fide. A little higher, oppofite to the cartilago-thyroides, it flernum.The right pericardia feems to go out rather from the gives off a tranfverfe branch, which tuns on the anterior origin of the right fubclavian, than from the trunk of and lower part of the rnufeuli fterno-maftoidsei, and comthe fuperior cava. It goes to the upper fide of the pe- municates with the jugularis of the other fide. ricardium,- and othermeighbouring parts. The fuperior and inferior tranfverfe branches commuThe right gutturalis or trachealis goes out from the nicate on each fide by branches more or lefs perpendicuupper part of th£ bifurcation, above the mammaria of the lar, and fend a fmall branch to the mufculus quadratus fame fide, fometimes more backward,' and foraetimes of the chin, to the mufculus cutaneus and integuments. from the fubclavia. It is diftributed to the glandulae It fends another ■ large branch anteriorly toward the thyroidaese, trachea arteria, mufculi fterno- hyoida;i, fymphyfis of the lower jaw, which, after having fupplithymus, and glandular bronchiaics. It communicates, ed the maxillary glands, is diftributed to the digaitric by lateral branches, with the internal jugular vein. The mufcle, to the chin and under lip. left gutturalis comes from the upper or poiterior part of Interiorly, at the fame place, it fends out a large branch* the left fubclavian, near its orign. which furnilhes the glandulae fublinguales,. runs down toThe.rjght fubclavian vein is verylhort, and its courfe ward the cornua of the os hyoides, to communicate with very objique, • fb that it appears to rife higher than the fome branches of the jugularis interna, and fends feveral left vein. It fends off, firft of all, four large branches, rami to the tongue, called vena ranina. It gives off viz. the.vertebralis, which is the firft and jnoft pofterior ; likewife a fmall branch, which running upon the mufcuthe jugularis interna, jugularis externa, and axillaris. lus labiorum triangularis, to the commiffure of the lips,' The left fubclavian feems to afcend but very little after is diftributed to the neighbouring parts. the bifurcation ; and, in this courfe, it covers the origin The fame branch which gives out the venae raninas,. of three large arteries, which come from the curvature detaches another to the lateral parts of the feptum palati, of the aorta. It fends off four large branches, befides which is diftributed to the amygdalae, and to the uvula, the fmall pedtoral veins, and receives the duftus thora- and fends rami forward to the membrane which lines the. cicus. arch of the palate. Another branch goes out from it to. It likewife gives off, before its principal divifion, a the pterygoidaeus internus, periftaphylini, and cephalofmall trunk for the left fuperior intercdftals, and this in- pharyngaei. tercoftal trunk furnilhes likewife the left bronchialis. Afterwards the trunk of the anterior external jugular Each fubclavian vein, near the middle of the clavi- vein runs up on the mufculus triangularis, where it recula, fends off a branch, called cephalica, which de- ceives tire name of vena triangularis, in a winding 'courfe, fcends near the furface of the body, between the del- from the angle of the lower jaw to the great or internal toides and, pedloralis major. angle of the orbit, fending branches on each fide to the Each external jugular vein arifes from the fubclavian mufcles and integuments. on the fame fide, fometimes from the axillaris, and fome- The trunk of the vena angularis having reached the times from the union of thefe two veins. They run up bones of the nofe, fends out a branch through the lateral between the mufculus cutaneus and fterno-maftoidaeus. c,artilages of the nofe, which is diftributed to the nar.es; Sometimes they are double from their very origins; and another which runs down in a winding courfe to the and when they are fingle, each of them divides after- upper lip. wards into two, one anterior, and the other pofterior, or At the great or inner angle of the eye, the fame trunk rather fuperior, The anterior vein goes to the throat fends off feveral other branches; the firft of which goes to