348 ANATOMY OF THE DOG. 
backwards if he is to have good wind, and the lateral diameter 
is of less importance. These facts ought to be taken into con- 
sideration in’ sélecting the best kind of ‘frame for the purposes 
of speed and endurance. phy jp 
Large size of bone contributes to the strength of the limbs, and 
foxhounds especially, which have continual blows and strains in 
their scrambling jover 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 so much lumber 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 fracture 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... - ‘ = 
The dog has no collar-bone, so that his fore-quarter is only — 
attached to the body by muscular tissue. This is effected ' chiefly 
by a broad sling of muscle, which is attached above to the edge 
of the shoulder-blade, and below to the ribs near their lower ends. 
It is also moved backwards by muscles attached to the spine, and . 
forwards by others connected in front to the neck and head, so 
that at the will of the animal it plays freely in all directions. 
The teeth are 42 in number, arranged as follows :— 
. 3-3 . 1-1 -6—6 
Incisors =: Canines |: Molars —: 
TEETH OF THE DOG AT VARIOUS AGES. 
The incisors are somewhat remarkable in shape, having three 
little lobules at their edges resembling a fleur-de-lis (Fig. 1). Next 
to these come the canine teeth or tusks, and then the molars, 
which vary in form considerably. In the upper jaw, in front, are 
three sharp and cutting teeth, which Cuvier ‘calls false molars ; 
then a tooth with two cutting lobes; and lastly, two flat teeth, 
or ¢rue molars. In the under jaw the first four molars on each 
side are false, or cutters; then an intermediate one, with the 
posterior part flat; and lastly, two tubercular teeth, or true molars. 
As the incisors are worn away and the dog becomes old, the 
