CIRCULATORY SVSTEIM. 205 



sends ramifications, and gets between the vastus interims and 

 rectus, where it spHts into two divisions which penetrate those 

 muscles. 2. Three or four small branches to the sartorius, 

 3. A long slender one to the side and front of the stifle. Its 

 posterior branches are — 1. A considerable one to the gracilis, 

 which detaches twigs to the long and short heads of the tri- 

 ceps. 2. A small one that turns inwardly to the vastus inteinus. 

 3. A branch supplying both the long and large heads of the tri- 

 ceps. 4. One that turns round the back of the bone, about the 

 middle of the thigh, for the supply of the biceps. 5. One large 

 or two smaller branches sent along the posterior border of the 

 gastrocnemius extern us, from which recurrent ramifications 

 ascend to the triceps. . At the back of the stifle come off the 

 popliteal branches, four or five in number, taking opposite di- 

 rections, which are destined for the supply of the stifle-joint: 

 one runs down upon the posterior tibial muscles ; another, the 

 recurrent Ora/icli, climbs the back of the os femoris, and anasto- 

 moses with the descending ramifications of the profunda femoris. 



The Tibial Arteries, 



Anterior and posterior, are to be regarded in no other light 

 than the bifurcated continuationof the femoral trunk: this division 

 takps place at the back of the head of the tibia. 



The posterior tibial artery, the smaller of the two, is 

 curved outward at its origin ; it then descends through the pos- 

 terior deep region of the thigh, inclining all the way, from the 

 outer to the inner side, at first running between the flexor pedis 

 and the popliteus (which is behind it) ; subsequently between the 

 former muscle and the flexor pedis accessorius; and at length be- 

 tween the tendon of the last-named muscle and the inner, poste- 

 rior, and inferior part of the body of the tibia. Just above the 

 hock, it inclines inward again, and gets deep-seated between the 

 lower end of the flexor pedis and the bone, where it ends in bifur- 

 cation. Jts branches are — 1. One, which comes oflf a short dis- 

 tance from its origin, and luns into the flexor pedis. 2. The 

 medullarij, which enters the medullary foramen, in the upper 

 and back part of the tibia. 3. Unimportant twigs to both the 

 flexors. Of its terminating branches— /f//e external one proceeds 

 round the outside of the hock, ramifying there subcutaneously, 

 and anastomosing with some articular twigs of the anterior tibial ; 

 the internal continues down the leg over the tendon of the flexor 

 pedis, within a cellular sheath formed between that tendon and 

 the root of the os calcis, in company with the internal metatarsal 

 nerve, and creeps along the inner edge of the metatarsal bone, 

 between the flexor tendon;:; and suspensory ligament, ending at 



