214 OUTLINES OF EQUINE ANATOMY. 



artery, passes over the annular ligament of the knee and 

 subsequently becomes internally placed to the inner splint 

 bone. At about the inferior part of the superior third of 

 the posterior surface of the large metacarpal bone it gives 

 off the medullary artery of that hone, and about at the bifur- 

 cation of the superior sesamoideal ligament it anastomoses 

 vfith a small recurrent hranch of the large metacarpal 

 artery, which we last noticed as being enclosed with the 

 nerves in the synovial sheath of the flexor tendons at the 

 back of the knee. It (the large metacarpal) passes doAvn 

 the back of the leg in contact with the inner margin of 

 these tendons, and subsequently between them and the su- 

 perior sesamoideal ligament, where it gives off the recurrent 

 branch, and then bifurcates to form the plantar arteries. 

 If we trace out one of these arteries we shall find that it 

 passes on to the lateral part of the fetlock, where it is sub- 

 cutaneous and where the corresponding vein is in front, the 

 nerve behind it. It gives off a large branch forwards, ramify- 

 ing in front of os suffraginis, and small unnamed branches 

 hacJctvards to the heel, and then runs directly to the internal 

 surface of the lateral cartilage. Just at the lateral part of the 

 cofiin- joint it gives two branches forwards and one back- 

 wards. The two running forwards anastomose with their fel- 

 lows from the opposite side at the front of the coronet, one 

 externally situated to the extensor pedis tendon being the 

 superficial coronoj^'y and sending on either side of the 

 tendon a branch inwards to the other, which being inter- 

 nally placed to the tendon is termed the deep-seated coro- 

 nary artery. The posterior hranch goes to the frog and 

 bifurcates, one of its branches running to the bulb, one to 

 the apex of that organ, each of them anastomoses with its 

 fellow. The plantars give off the lateral laminal arteries, 

 while running over the internal surface of the lateral car- 

 tilages, and these pass outwards through the foramen in 

 the wing of the os pedis (or between os jDedis and the 

 cartilage), running forwards in a groove to anastomose at 

 the front of the bone with each other, and giving branches 

 superiorly to the coronary arteries, inferiorly to the circum- 

 flex artery of the toe, and inwards to the arterial circle 

 formed in the substance of os pedis by the anastomosis of 

 the two plantars, which, after jmssing through grooves on 

 the under surface of os pedis between the inferior broad 

 ligament of the navicular bone and the perforans tendon, 



