22 VETERINARY STUDIES 



hoof. It assists the horny frog in lessening jar in travel and 

 protects the insertion of the deep flexor tendon. 



"Back tendons." — This is a term used by horsemen to include 

 the tendons of the superficial and deep flexor muscles of the foot 

 and the suspensory ligament. 



The superficial flexor muscle, of the front foot, has its origin 

 on the lower end of the humerus and its insertion by tendon on 

 the sides of the second phalanx. Its function is to flex the foot 

 at the first interphalangeal articulation. 



The deep flexor muscle, of the front foot, has its origin in 

 common with the superficial flexor on the lower end of the 

 humerus, and its insertion by a tendon which spreads out on 

 the sole of the third phalanx. Its duty is to flex the second and 

 to assist in flexing the first interphalangeal articulation. 



The suspensory ligament is broad and very strong. It at- 

 taches by its upper end to the carpal bones and to the large 

 metacarpal. Its lower end divides into two branches which pass 

 forward on each side and attach to the front tendon. Its duty 

 is to support the metacarpo-phalangeal articulation (fetlock). 



Practical application. — The shape and peculiar characteristics 

 of each hoof correspond by correlation with the remainder of 

 the limb, except as the hoof has been varied by artificial means. 

 So in judging the hoof it is also necessary to consider the char- 

 acteristics of the entire limb. 



The front limb may be said to be normal in position and direc- 

 tion when it appears on front view that a vertical line from the 

 front of the scapulo-humeral articulation passes down the center 

 of the limb and to the ground at the center of the toe. 



On viewing such a limb from the side it should be evident 

 that a vertical line downward from the bony prominence at the 

 middle of the scapula would divide the external surface of the 

 limb into two equal portions and reach the ground immediately 

 back of the heels. 



Viewing the hoof and pastern alone it should be seen that the 

 hoof is in direct line with the pastern and metacarpal or meta- 

 tarsal bones, and that a line extending from the center of the 

 cannon through the center of the pastern would pass through 

 the center of the toe. 



The hind limb when viewed from behind should show that a 

 vertical line downward from the prominence at the posterior 

 portion of the pelvis on each side (tuberosity of the ischiiun) 



