12 THE VETERINARY SCIENCE. 



Liie round joint and also helps to form the upper wall of the pelvic 

 or hip cavity. The ischium passes back from the round joint and 

 helps to form the floor of the pelvic cavity, and can be felt in a 

 horse that is poor in flesh projecting- out below the tail on each side. 

 The pubis, the smallest of the three bones, is situated immediately 

 in front of the ischium bone and forms the floor of the pelvic cavity. 



STERNUM OR BREAST BONE. 



This bone is small and short in the horse and is situated on 

 the lower side of the chest cavity. The principal points of this 

 bone are that it is the softest one in the horse, and the first eight 

 pairs of ribs are attached to it on either side. This bone, in the 

 horse, resembles a small, flat boat. 



RIBS. 



In considering the ribs we find eighteen pairs. They form 

 the lateral wall of the thorax or chest cavity and aff"ord protection 

 to the heart and lungs. They are attached above to the dorsal 

 region of the back bone. Below, the first eight pair are attached 

 to the sternum, or breast bone ; these are called the true ribs of 

 the horse; the next ten pair are not attached to the sternum 

 below, the lower ends being free, and are continued downwards 

 and forwards by a small piece of cartilage or gristle, and are just 

 slightly attached to the breast bone ; these are called the false ribs. 

 Also remember that, starting with the first rib, they get longer 

 until we get to the ninth rib ; afterwards they get shorter until the 

 last rib is reached, it being only a few inches long. 



NUMBER OF BONES IN SKELETON OF HORSE. 



In the head of the colt is found thirty-eight bones, not includ- 

 ing the teeth, but in after life we find a great many bones become 

 attached to each other by a process called ossification. 



Head 38 



Spinal column 54 



Pelvic cavity or hips, three pair or six single (j 



Ribs, eighteen pair 86 



Breast 1 



Both front legs 42 



Both hind legs 36 



Ear, bones very small and unimpoitaut 3 



Total, not including the teeth 216 



The teeth are dealt with separately in another section of this book. 



