38 STRUCTURE AND ECONOMY OF THE HORSE. 



rest being arranged in pairs, so that both sides of the body cor- 

 respond, whereby symmetrical appearance is preserved. 



These muscles have been arranged by anatomists into various 

 classes, according to their relative situation. Thus, we have the 

 muscles of the head, the trunk, and the extremities, and these, 

 jigain, are divided into various regions. 



Under that of the head we have nine muscles, whose office is 

 to move the ears ; two attached to the eyebrows, eight to the 

 eyes, and no less than seventeen connected with the jaws, twelve 

 of which belong to the anterior and five to the posterior jaw. 

 And between the jaws, the submaxillary space as it is called, 

 there are twenty-four small muscles, six of which are connected 

 with the OS hyoideus, the curious bone at the root of the tongue; 

 four belong to the tongue, five to the pharynx, seven to the 

 larynx, and two to the palate. 



The muscles of the Trunk, one hundred and thirteen In num- 

 ber, are divided into those of the neck, the thorax, and the abdo- 

 men. The muscles of the neck are forty in number, and are 

 divided into five regions. 



The muscles of the Thorax are thirty-seven in number, and 

 are divided into seven regions, of which we have three muscles 

 connected with the shoulder and the back, three with the chest, 

 three with the ribs, three with the breast bone, and three with 

 the back and ribs ; besides which, we have three large muscles 

 on the back, one of which, the longissimus dorsi, is of great 

 size and length, extending on each side of the dorsal spine 

 almost the whole length of the back, of which it forms the prin- 

 cipal strength : it is particularly observable in stout fleshy 

 hox'ses. 



The seventh region of the thorax is composd of one muscle, 

 the diaphragm, which separates the thorax from the abdomen, 

 and is the principal agent in respiration, acting independently 

 of the will. 



The muscles of the Abdomen are thirty-six in number in the 

 male, and three less in the female, and are divided into five 

 regions. There are six muscles belonging to the loins, four to 

 the abdomen itself, their office being to support its contents and 

 to assist in respiration; two muscles belong to the anus; four to 

 the Genital region in the male, and two in the female; and four 

 muscles are connected with the tail. 



The muscles of the Anterior Extremity are forty-eight in 

 number, and are divided into eight regions. 



Thei-e are twelve muscles connected with the shoulder, two on 

 the outside of the blade, one being in front, and the other behind 

 its spine. One muscle connects the shoulder blade to the ribs, 

 and two others are attached to the back part of the scapula and 

 to the humerus. Two muscles are attached to the lower and 



