40 



THE HORSE IN HEALTH AND DISEASE 



shaft and two extremities. The internal surface of the shaft is 

 straight, not covered with muscle, and corresponds to the shin of 

 man ; the external surface curves to the front of the bone, where it 

 becomes flattened; the posterior surface presents several rough 



Fig. 5. — Right tarsus and proximal part of metatarsus: Tt, Tibial tarsal 

 bone; Tf, fibular tarsal; Tc, central tarsal; T3, third tarsal; T'f, fourth tarsal; 

 1, tuber calcis; 2, tuberosity of tibial tarsal; 3, vascular canal; 4, groove for 

 artery; Ml. Ill, Ml. IV, metatarsal bones. (Sisson, Anatomy of Domestic 

 Animals.) 



ridges and the nutrient foramen. The anterior border is promi- 

 nent and forms the tibial crest. The upper extremity is large, 

 three sided, and shows two saddle-shaped surfaces for articulation 

 with the condyles of the femur; centrally there is a pointed promi- 

 nence; externally there is a rough facet for the head of the fibula. 



