plantar surface of the hoof
Corneous lower surface of the hoof in contact with the ground.
lateral groove 
Natural groove separating the frog from the bars and the sole.
sole 
Strong thin corneous plate comprising the lower portion of the hoof and resting on the ground.
wall 
Corneous material making up the perimeter of the hoof; it is produced by the coronet and grows from 0.3 to 1 in a month.
white line 
Line of dense compact corneous material bringing together the sole and the inner edge of the wall of the hoof.
toe 
Front part of the wall of the hoof between the side walls and opposite the heel.
side wall 
Side part of the wall of the hoof between the toe and the quarter.
quarter 
Side part of the wall of the hoof between the heel and the side wall.
bar 
Terminal part of the wall of the hoof running along the edge of the frog.
frog 
Part of the hoof made of soft but strong corneous material located in the notch of the sole; it is used to absorb shocks and sense the terrain.
heel 
Rear portion of the wall of the hoof between the quarters and opposite the toe.
bulb 
Corneous eminence ending at the frog and joining with the heel.