THE HORSE ANA TOM Y A ND PH YSIOLOG Y. 



CHAPTER IV. 



THE HORSE AN ATOMY AND I'HYSIOLOQY. 



THE horse may be conveniently considered as a system of or- 

 ganisms, each having a special function or work to per- 

 form in the animal economy. 



1. The bony system or skeleton, which is the frame-work. 



2. The muscular system, which may be considered as the 

 cords or tackling to move the frame- work. 



3. The nervous system, which includes the brain and controls 

 all other organs. 



4. The digestive system, which prepares nourishment for 

 the body. 



5. The circulatory system, which is a system of canals for 

 tranmission of nourishment to all parts of the organism. 



6. The excretory system, by which the unused matter is elim- 

 inated from the body. 



7. The generative system, or organs, by which are begotten 

 and delivered into the world the young of the species. 



THE SKELETON. The frame of bones of the horse comprises 

 two hundred and forty-seven bones, distributed as follows : 



1. In the skull, 10. 



2. In vertebral column 48, divided as follows : Cervical, or 

 neck, 7; dorsal or back, 18; lumbar or loins, 6 ; caudal or tail, 17. 



3. In the face and jaws as follows : In face and lower jaw, 

 18; in each ear, 4; tongue, 5; teeth, 40. 



4. In thorax or the chest, 37. 



5. In pelvis, 3. 



6. Bones of locomotion, 40 in front and 38 behind. The 

 bones of locomotion in front include the scapula, humerus, 

 os brachii, carpal bones, metacarpals, os suffraginis, os coronoe, 



