206 CIRCULATORY SYSTEiM. 



the lower part of the cannon in divers sniall ramifications. At 

 the hock, this artery sends off" one or two recurrent branches, which 

 ascend upon the back of the os calcis, and anastomose with others 

 coming down from the posterior tibial. 



The anterior tibial artery no sooner leaves the common 

 trunk, than it suddenly turns forwaid, and passes between the 

 tibia and fibula towards the fore part of the thigh. Next we 

 find it between two veins, crossing with very gradual obliquity 

 the outer part of the bone to gain the front, which it does about 

 midway between the stifle and hock ; it then continues to descend 

 between the outer border of the flexor metatarsi and the bone 

 until it reaches the front of the hock, where it makes another 

 sweep outward, and ultimately arrives in the channel between the 

 external and large metatarsal bones, in which situation it becomes 

 the metatarsal artery. Its branches are — 1. Some small recur- 

 rent articular, ascending to the stifle and communicating with 

 the popliteal branches. 2. Various muscular branches, in its 

 course down the thigh. 3. Divers, small, articular and cuta- 

 neous branches, as it obliquely winds from the front of the hock 

 to its outer and anterior part, 4. A slender metatarsal artery 

 which descends upon the front of the cannon, in close connexion 

 with the bone, along the inner border of the extensor tendon, 

 whose ramifications, mostly cutaneous, are distributed over the 

 inner and fore part of the leg, the terminating ones reaching as 

 low as the fetlock. 



The metatarsal artery pursues its course, unaccom- 

 panied by any vein, along its (above-noticed) channel, for two- 

 thirds or thereabouts of the length of the leg ; it then passes 

 between the internal and large metatarsal bones, and gains the 

 posterior part of the latter, between which and the suspensory 

 ligament, a little above the fetlock, it divides into three vessels : 

 one forms an arch (as in the fore extremity) sending oflT the recur- 

 rents, which anastomose with the posterior tibial artery ; the other 

 two — the lateral divisions — become the plantar arteries. 



Henceforward, the arteries in the hmd leg are similar in all 

 respects to those in the fore extremity : the description already 

 given of the latter, therefore, will be found equally applicable 

 here. 



