40 STRUCTUEE AND ECONOMr OF THE HORSE. 



latter, have a common origin from the inner and inferior part of 

 the humerus, become two separate tendons above the knee, and 

 are inserted, the i)erforatus into the small pastern, and the per- 

 forans into the cothn bone. 



A third muscle is attached above to the back part of the 

 radius, and below joins the perforans tendon, which it assists. 

 Besides these, there are some diminutive and insisz;nificant mus- 

 cular slips below the knee. 



The muscles of the Hind Extremity are more numerous than 

 those of the fore limb, and are divided into those belonging to 

 the haunch, and those of the thigh and hind leg; of the former 

 there are twenty, and of the latter nine. 



There are three very large and powerful muscles, called the 

 gluteal, which are attached above to the haunch bones, and 

 below to the upper part of the femur or thigh bone. These 

 muscles are of great importance in progression, as by their 

 action they advance the body after the limb has been brought 

 forward : they also act in both kicking and rearing. In man, 

 they are still larger in proportion than in quadrupeds; and they 

 mainly assist in preserving the erect position of the body. In 

 fat horses these muscles aj^pear externally mingled together, 

 but in well-bred animals, particularly if they have been trained, 

 the lines, or rather the furrows, of demarcation are readily per- 

 ceptible. It is needless to observe, that these muscles form the 

 greater part of a haunch of venison, and in deer are more 

 largely developed than in sheep. 



There are four smaller muscles, attached below to the upper 

 part of the thigh bone, and above to the under parts of the 

 haunch bone, their office being to assist in the extension of the 

 haunch, and, in some measure, to I'otate it : some of them are 

 situated within the pelvis, and are connected with the peri- 

 toneum. 



There are three muscles which form the front part of the 

 haunch. One rises from the spine of the ilium, the hip bone, 

 and is inserted into the membranous covering of the muscles of 

 the thigh, whence it is called the tensor vagince, and is very per- 

 ceptible in poor horses. 



Another large muscle is attached to the ilium above and pa- 

 tella below, and is called the rectus. 



The third muscle is of great size, and has three divisions, 

 vv^hich are often considered as separate muscles. Each of these 

 heads are inserted into the patella below, but above, two are at- 

 tached to the femur, and one to the bones of the pelvis. 



These powerful muscles, although not attached to the tibia 

 itself, are yet connected with it by means of the patella, and 

 thus become powerful extensors of the thigh, raising and ad- 

 vancing the limb, and assisting in the progression of the haunch. 



