HORSESHOEING. 



35 



E. The Blood- Vessels and Nerves. 



Vessels which carry blood from the heart to the tissues are 

 called arteries, while those which return the blood to the heart 

 from the tissues are called veins. Arteries and veins are con- 

 nected by very small, thread-like 

 vessels called capillaries, which 

 originate in the smallest arteries 

 and are so minute that they can 

 not be seen without the aid of 

 a microscope. The capillaries 

 penetrate the soft tissues in every 

 direction, and finally unite to 

 form small veins. For our pur- 

 pose we need consider only the 

 arteries and veins. 



The arteries carrying blood 

 from the heart ramify and subdi- 

 vide in all parts of the body, and 

 thus reach the foot. They are 



Eight forefoot "viewed from below, behind, 

 and the external side. This figure shows 

 clearly the position of the plantar cushion. 

 The external lateral cartilage and the tissues 

 covering the plantar cushion and under sur- 

 face of the OS pedis (velvety tissue of the sole 

 and fleshy frog) have been removed : a, fleshy 

 frog or plantar cushion ; a', bulbs of plantar 

 cushion ; the remaining visible parts belong to 

 the so-called " fleshy frog ;" a", groove (median 

 lacuna) in the lower surface of the fleshy frog, 

 in which lies the frog-stay of the homy &og ; 

 &, suspensory ligament of the plantar cushion 

 passing out of the bulbs ; V, small elastic cords 

 passing to the lateral cartilage ; c, elastic liga- 

 ment coming from the lateral cartilage and 

 uniting with the suspensory ligament of the 

 plantar cushion ; d, small tendinous cord be- 

 ginning in the slcin behind the fetlock-joint 

 and ending on the os suffraginis in common with b and c ; e, tendinous reinforcing sheath of 

 the perforans tendon ; /, reinforciug stay of the perforatus tendon ; g, perforatus tendon ; h, 

 perforans tendon ; i, suspensory ligament of the fetlock ; k, plantar surface of the os pedis, to 

 which the plantar cushion is joined by fibrous bands. 



