PRINCIPLES OP IMPROVING DOMESTIC ANIMALS. 



brsB ; e e the sacral vertebraj ; and f is the caudal 

 vertebrae, or bonea of the tail. With the vertebral 

 column are connected, (1) the ribs Hi (2) the scapu- 

 la or shoulder-blade g-; (3) the bones of the pelvis -p. 

 With the shoulder-blade are connected the fore-limbs, 

 consisting, (1) of the humerus or great bone of the 

 shoulder k ; (2) the fore arm I m, of which m is the 

 elbow; (3) of the bones of the carpus or knee n ; 

 (4) of the cannon-bone or shank o ; and (5) of the 

 bones of the pastern and foot (6). With the pelvis, 

 p, are connected the bones of the posterior limbs, 

 namely, (1) the femur or great bone of the thigh q ; 

 (2) the patella or stifle-bone r ; (3) the tibia or great 

 bone of the leg s ; (4) the bones of the hock t ; (5) 

 the cannon-bone m ; (6) the bones of the pastern 

 and foot 6. 



It is from the dorsal vertebrae, or bones of the 

 back, that the ribs proceed, forming hoops which en- 

 close the chest and a part of the abdomen. « 



The number of dorsal vertebra', and consequently 

 of the ribs, on each side, is eighteen, but sometimes 

 one, or even two more are developed. The ribs are 

 mostly connected by cartilaginous bands with the 

 scapula or breast-bone of which the upper termina 

 tion, h, appears in the figure. The breast-bone, fiat 

 and of a spongy consistence, is formed of several 

 pieces united together, and is sometimes likened, from 

 its form, to the keel of a ship. The chest contains 

 the lungs and heart, and is separated by a muscular 

 partition from the abdomen, which contains the liver, 

 the stomach, the intestinal canal, the kidneys, and 

 other organs. 



The shoulder-blade or scapula g, of which there 

 is one on each side of the chest, is a flat triangular 

 bone, with its narrow end pointing obliquely down- 

 wards. It is attached to the chest by intervening 

 muscles, and strengthened in its position by other 

 powerful muscles with which it is connected. Into a 

 shallow cavity at the lower part of this bone, is in- 

 serted the humerus or bone of the shoulder. The 

 humerus corresponds with the bone of the same name 

 in man, that is, with the portion of the human arm 

 which is between the elbow and shoulder, but is so 

 covered with muscles in the horse, as to seem to form 

 a part of the trunk. It is bent downwards and back- 

 wards in a direction opposite to that of the shoulder- 

 blade, by which disposition the parts act hke a spring 

 to lessen the effects of those terrible shocks which 

 they sustain, when the animal being raised from the 

 ground, his iveight is received upon his fore extreme- 

 lies. The head of the humerus working in a very 

 .shallow cavity in the shoulder-blade, the bone has 

 great freedom of motion. Its lower extremity is 

 fitted by a hinge-like joint into the next in order of 

 ihe bones of the limb, namely, the bone of the fore- 

 arm. 



The bone of the fore-arm corresponds with that 

 portion of the human arm which is between the elbow 

 and the wrist, but the fore-aim in the human subject, 

 consists of two bones, termed respectively, radius 

 and ulna. In the horse, tlicre were likewise two 

 bones in the young state, but they became joined 

 together; though the ulnar ]iortion, as in the figure, 

 is still to be distinguished projecting behind the up- 



