CHAPTER I. 



PECULIARITIES IN THE ANATOMY AND PHYSIOLOGY 

 OF THE DOG. 



r 

 THE SKELETON, INCLUDING THE TEETH. — THE MUSCULAR SYSTEM.— THE 



BRAIN AND NERVOUS SYSTEM. — THE DIGESTIVE SYSTEM. — THE HEART 



AND LUNGS.— THE SKIN. 



THE SKELETON, INCLUDING THE TEETH. 



In the skeleton of the dog and in that of the horse, as well as of all 

 other animals remarkable for their speed, there is a peculiar char- 

 acteristic of the chest which deserves to be noticed. A narrow- 

 chested horse or dog may have better wind than another with a 

 round barrel, because he is able to alter the cubic contents of his 

 chest more rapidly, and thus inspire and expire a larger volume of 

 air. A medium transverse diameter is therefore to be desired 

 and is practically found to be advantageous, in allowing a better 

 action of the shoulder-blades rolling upon the surface on eacb 

 side. These facts ought to be taken into consideration in selecting 

 the best kind of frame for the purposes of speed and endurance. 



Large size of bone contributes to the strength of the limbs, and 

 foxhounds especially, which have continual blows and strains in 

 their scrambling over or through fences of all kinds, require big 

 limbs and joints. When, however, extreme speed is desired, as in 

 the greyhound, there may be an excess of bone, which then acts as 

 an incumbrance, and impedes the activity. Still, even in this dog, 

 the bones and joints must be strong enough to resist the shocks of 

 the course, without which we constantly find them liable to frac- 

 ture or dislocation. If, however, a dog is brought up at liberty, 

 and from his earliest years is encouraged in his play, the bones, 

 though small, are strong, and the joints are united by firm ligaments 

 which will seldom give way. 

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