64 ANATOMY AND PHYSIOLOGY. 



the cannon through the center of the pastern would pass through 

 the center of the toe. 



The hind hmb when viewed from behind should show that a 

 vertical line downward from the prominence at the posterior por- 

 tion of the pelvis on each side (tuberosity of the ischium) would 

 divide the entire limb into two equal portions and reach the 

 ground back of the center of the horny frog. 



Viewed from the side the normal hind limb should indicate 

 that a vertical line, dropped from the prominence of the articu- 

 lation between the femur and pelvis, should reach the ground op- 

 posite a point near the center of the hoof. This line is somewhat 

 difficult to get, and of less value for the reason that a slight 

 leaning forward or backward disturbs it. This should be taken 

 when the horse is standing with the limb squarely under the 

 body in a natural position for the particular animal examined. 



For the front hoof the wall at the toe and the anterior sur- 

 face of the pastern, should make an angle of not less than 45 nor 

 more than 50 degrees with the level ground surface. The wall 

 at the toe and the anterior surface of the pastern having the 

 same slant. 



For a normal hind hoof the angle should be from 50 to 55 

 degrees, and the anterior faces of the hoof and pastern should 

 still have the same slant. 



A normal hoof has a good quality of horn, wide heels, and 

 circular rather than long and narrow ground surface. The hind 

 hoof is narrower and more pointed at the toe than the front 

 hoof. The zvall from coronary band to ground surface should 

 be straight and smooth; i. e., no ridges or grooves. The heels 

 should be rounded, well developed and of the same height at 

 the top of the coronary band. The sole should be distinctly con- 

 cave and show no marked separation from the wall. The frog 

 should be large, elastic, the two portions of the same size, with 

 a shallow groove along the center. The bars should be straight, 

 extending forward and inward. The lateral cartilages, felt above 

 the coronan' band on each side, should be elastic. The sole in 

 the angles between the bar and wall at the heel should not sliow 

 red stain. There should be no separation of the horny fibers 

 as in toe or quarter cracks. The wall should be reasonably thick. 

 This can be usually determined by tapping the wall with a ham- 

 mer, noticing- its rigidity. 



