THE THIRD OR DISTAL DIGITAL BONE may be compared to a cone that has been cut away posteriorly, obliquely downwards and backwards. The superior face shows two shallow cavities that are completed posteriorly by the superior face of the coffin or navicular bone. The anterior face is convex and cribbled by openings, and the inferior face is concave, forming the sole. Tendons belonging to the digital muscles terminate on the summit and inferior face of this bone. THE PELVIS OR HAUNCH is formed by a single bone, the _coxa_ that in the foetus may be divided into three bones. These are the _ilium, pubis_ and _ischium_. It belongs to the class of flat bones. Anteriorly it is flattened from before to behind and directed inward and upward. The external angle is rugged and is generally termed the angle of the haunch. The internal face of the opposite angle articulates with the sacrum, to which it is firmly attached by ligaments. The middle portion is constricted and forms a neck. The inferior or posterior portion is flattened from above to below, and directed inward to meet the border of the opposite bone. Just below the neck and externally, there is a cup-shaped cavity into which the head of the thigh bone fits. The two coxa, together with the sacral ligaments (sacrum) and the muscles of the quarter, enclose the pelvic cavity. THE REGION OF THE THIGH is formed by the _femur_, the largest long bone in the body. The superior extremity is formed by a rugged eminence, to which the heavy muscles of the quarter are attached, and by an articular head. The inferior extremity is formed by two convex articular surfaces that are separated by a deep notch, and a third pulley-like articular surface, with which the patella or knee-cap articulates. The pair of condyles articulates with the superior extremity of the leg bone. The thigh or femoral region is heavily muscled. THE LEG is formed by three bones. The patella, a short bone, has already been mentioned as articulating with the thigh bone. The tibia and fibula are the other two bones in the region. THE TIBIA belongs to the class of long bones and the fibula is quite rudimentary, being represented by a stylet-shaped bone that lies posterior to, and along the outer border of the tibia. The superior extremity of the tibia shows a central spine margined laterally by rather plain articular faces. It articulates with the thigh bone. The muscles of this region are divided into two sub-regions, _anterior_ and _posterior_ tibial. The muscles originate from the lower extremity of the femur and the two bones in this region, and terminate inferiorly in tendons that are attached to the bones of the hock, cannon and digit.