EXTERNAL FORM. 



Ixxvii 



is designed for the attachment, and passing over it, of ten- 

 dons of muscles. 



Jointed to the lower part of the femur is the tibia, or great 

 bone of the leg, connected with which, by ligamentous mat- 

 ter, is the small bone termed the fibula. These two bones 

 form properly the leg of the horse ; but they are, in popular 

 language, termed the thigh, although they correspond, not 

 with the bone of the thigh in the human species, but with the 

 leg. 



Next to these bones are those of the hock, which corre- 

 spond with the bones of the ankle or instep in man ; and on 

 one of them the tibia works by means of a hinge joint. They 

 are six in number, and one of them, corresponding with the 



Fig. 4. 



great bone of the heel in man, pro- 

 jects backwards, and has powerful 

 muscles for extending the limb in- 

 serted into its extremity, so that it 

 acts as a strong lever in aiding the 

 forward motion of the animal ; and, 

 as in the fore extremities we look to 

 the size of the elbow as a point to 

 be regarded, so, in the posterior 

 limbs, we look to the size of the 

 bone of the heel. 



The next bones below correspond 

 entirely with those of the fore extre- 

 mity. They are, (1.) the cannon- 

 bone, or shank, with the two splint- 

 bones attached ; (2.) the pastern ; 

 (3.) the coronet bone ; (4.) the cof- 

 fin bone, with the sesamoid and na- 

 vicular bones, as in the fore extre- 

 mities. These several bones of the 

 hinder limb are represented in the 

 annexed figure, where pp are a part 

 of one of the pelvic bones, q the femur, r the stifle bone, 



