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 244 A N A T O -M Y. Part IV. lung t'n - raftcrillcebetween the fitft two metatarfal bones branches, called tibialis anterior, tibialis pojlerior, and tov/ard the great toe, where this vein terminates. peroncea. The crural vein, having lent off the laphena, and the The anterior tibial vein, having diftributed fome fmall fmall branches for the pedhneus, <&c. as has been laid, branches from its very beginning to the mufcles behind runs down on the thigh behind the crural artery. Op- the heads of the two bones of the leg, perforates the inpoiite to the -little trochanter, it produces two large terofleous ligament from behind, forward, and runs befiiort branches, or one which afterwards divides into two, tween the fuperior portions of the mufculus tibialis antiwhereof one is anterior, the other pollerior. cus, and extenfor digitorum communis. The anterior branch runs more or lefs tranfverfely As foon as it pierces the interofleous ligament, it diforward, to be ditlributed to the vaftus internus, lower ftributes fmall fuperficial branches to the head of the tipart of the pe&ineus, and of the fecond triceps, and to bia and fibula, which run to the joint of the knee, and the other two mufcles of the fame name, running in be- communicate with the lateral branches of the vena potween them as it goes from one to another. plitea. The p often or branch runs more or lefs tranfverfely Afterwards it divides into two or three branches, backward, and furniihes the glutei, vaftus externus, and which run down together on the forefide of the interofbeginning of the biceps. feous ligament in company with the anterior tibial arteA little below thefe two branches, about the upper ex- ry, which they furround at different diftances, by fmall tremity of the vaftus internus, the crural vein produces a communicating circles. branch which runs down on the fide of the trunk, co- Thefe branches having reached the lower extremity of vering the crural artery, almoft as low as the ham, where the leg, unite in one, which afterwards divides into feveir is again united to the trunk by an anaftomofis. It has ral, the ramifications of which are diftributed to the foot. the name of vena fciatica, from the fciatic nerve which The pofterior tibial vein gives off, from its beginning, a branch toward the infide, which is diftributed to the it accompanies. On the outfide of this anaftomofis, the crural vein gaftrocnemii and foieus. This vein is named furalis. gives off a branch which runs backward between the bi- Afterwards the pofterior tibialis runs down between ceps and neighbouring mufcles, a*d fo downward on the the foieus and tibialis pofticus, giving branches to each backfide of the leg a little exteriorly, and very near the of them. It is divided in the fame manner as the tibiIkin, all the way to the outer ankle. This vein is term- alis anterior, into two or three branches, which, as they run, furround the correfponding artery, by fmall ed faphena minor, or externa. The little faphena, having got near the integuments communicating circles formed at different diftances. in its courfe downward, gives out a branch which runs It continues this courfe in company with the artery as backward, and communicates with the great faphena a- low as the outer ankle, furnifhing the mufeulut; tibialis pofticus, and the long flexors of the toes. bout the middle of the backfide of the thigh. Immediately above and below the ham, this vein fends Laftly, it paffes on the infide of the os calcis, under out other branches, which likewife communicate with the foie of the foot, where it forms the vense plantares, the faphena major, and, having run down about one by dividing into feveral tranfverfe arches, which comma • nicate with each other, and with the faphena, and fend third part of the backfide of the tibia, it fends off another ramifications to the toes. branch, which is afterwards re-united to the trunk. About the beginning of the tendo-achillis, the little The vena peronsea is likewife double, and fometimes faphena runs outward in the integuments, toward the triple. It runs down on the infide of the fibula, which outer ankles, where it terminates in cutaneous ramifica- it likewife furrounds at different diftances, by communicating branches, after the manner of the tibialis pofterior. tions fen t to every fide. The crural vein, having detached the little faphena, It runs down as low as the outer ankle, communicating runs down between the biceps and the other flexors of feveral times with the tibialis pofterior, and fending ramithe leg, clofely accompar.ied“'by the crural artery, be- fications to the neighbouring portions of the mufeuli petween which and the inner condyle of the os femoris it ronssi, and long flexors of the toes. The vena porte is a large vein, the trunk of which is is fituated. A little above the ham, it takes the name of vena po- fituated chiefly between the eminencies on the lower or plitea; and as it runs down betwixt the two condyles, it concave fide of the liver. gives branches to the flexor mufcles, to the lower and It may be confidered as made up of two large veins, pefterior parts of both vafti, and to the fat which lies a- joined almoft endwife by their trunks, from each of which the branches and ramifications go out in oppofite bove the interfaces of the two condyles.It likewife gives off feveral other branches, one of directions. One of thefe trunks adheres to the liver, which runs up laterally between the outer condyle and and is ramified in that vifeus, its branches accompanying the biceps, and then turning forward, is ramified in the the whole diftribution of the hepatic artery. The other trunk is without the liver, and fends its fame manner with the artery. The vena poplitea runs down immediately behind the branches to the vifeera, fupplied by the reft of the artemufcle of the fame name, at the lower part of which it ria csliaca, and by the two mefenteriae, that is, to the fends off feveral ramifications to each fide, which di- ftomach, inteftines, pancreas, fpleen, mefentery, 1 and ovide and unite again in different ways; and afterwards it mentum. lofes its name, being divided into three confiderable The firft portion of this vein may be termed poriee vena