CHAPTER m. 



THE MUSCUTx^R SYSTEM AJSTD INTERNAI, PUKCTIONS OF THB 



HORSE. 



TSE ECONOMY OP THE MDSCULA.K COVERING. 11. MUSCLES OF THEJaEAD AWD 



TJECK. III. MUSCLES OP THE SHOULDER AND BACK. IV. MUSCLES OF THE 



HINDER PARTS. Y. MUSCLES OP THE FORE LIMBS. VT. MUSCLES OF THE LEO 



AND FOOT. VII. STUDYING THE STRUCTURE. VIII. INTERNAL ECONOMY OF THE 



:10RSE. IX. EXTERNAL PARTS OF THE HORSE. 



I. The Economy of the Miiscular Covering. 

 While, as already stated, the bones are the frame-work of the animal, 

 the covering of the bones, viz : the sinews, muscles, nerves, membranes r 

 etc., are really what constitute the motive power of the animal. With the 

 nerves and membranes we shall have little to do ; their study will not be 

 necessary to a correct understanding of the value of a horse to the 

 farmer, breeder, or buyer. The bony and muscular development being 

 perfect, and the digestive apparatus, the viscera, and all that pertains there- 

 to., being healthy , the nerves and membranes may be taken for granted £is 

 being in good order. We therefore proceed at once to a consideration of the 

 more important organs which constitute the working parts of the horse. 



This we have most carefully illustrated on the next page by a cut, show- 

 ing the entire figure of the horse with the principal muscles laid bare. 

 They need not be referred to here, since they will be named further on in 

 considering the illustrations of the several parts. The engraving is 

 considered necessary, as showing the connection of the parts, one with 

 another, as the animal appears in walking. 



A Vertical Section of the Head. — A section of the head may here bc^ 

 studied to advantage, as showing not only the bony and muscular struc- 

 ture, but the brain and ganglia as 

 well. In the study of this figure we find 

 at a, the frontal bone, showing the 

 cavity or channel, (sinus) beneath; 

 6, the wall bone (parietal) covering 

 the brain; c, the nose (nasal) bone; 

 (?, the bone (occipital) at the back of 

 the head ; e, e, the first bone of the 

 neck, (atlas) showing the spinal mar- 



„ , „ . „ _ , row in the center ; /*, the sieve-like 



Cut 1. Horse's Head, Open TO View. . , .,x i. J, ^ i . ,. xi. 



(ethmoia) bone through which the 



nerve, (olfactory) giving the sense of smell passes ; g, the wedge-like 



hone, (spJienoid). This, with the ethmoid bone, supports the base of 



th'^ brain. At A, between C and D is shown part of the lower, (max- 



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