THE CAT'S PLACE AY MATURE. 



353 



points, which are adherent to the true rib 

 terminations, for support. 



The Sternum, or breast-bone, consists of 

 eight bones, from each joint of which springs 

 a rib-like costal cartilage, to which the true 

 ribs are articulated. The cat's collar-bone or 

 clavicle is very short and rudimentary ; it has 

 a slight attachment to the acromion process of 

 the scapula, the other end terminating in the 

 muscles of the chest. It is often absent. 



The Appcndicular Skeleton includes the fore 

 and hind limbs. The fore limb in the cat, as 

 in the majority of mammals (see plate, 

 P- 355 )> i s a subtriangular flat bone, with 

 a ridge on the outer side for the attach- 

 ment of certain muscles moving the leg. 



In a small hollow on the posterior 

 or lower border is articu- 

 lated the head of the 

 hnmcrus (4), or arm-bone ; 

 its lower or distal end is 

 expanded, and receives the 

 end of the ulna (10), which 

 with the radius (9) forms 

 the bones of the forearm. 

 The wrist or carpal bones 

 (8) include seven small 

 bones, the upper row being 

 attached to the radius, the 

 lower row to the five pha- 

 langes of the toes (7) ; to these latter are 

 articulated the bones of the digits, or fingers. 



The terminal 

 bones of the cat's 

 foot arc encased 

 by powerful 

 hooked claws 

 (Fig. in.). When 

 at rest, the claw 

 is brought to the 

 outer side of the 

 middle phalanx 

 by the elastic 

 ligament F, the 

 flexor tendons 

 being relaxed. 



KIG. VI. C. CATS SKULL FROM c 



i:i-:i.o\v, WITHOUT LOWER JAW, "'hen the cat is 

 SHOWING PALATAL SURFACE. on the point of 

 23 



FIG. VI. . CATS SKULL' 



VIEW FROM ABOVE. 



FIG. \i.b. CAT'S 



WITH LOWER 



seizing its prey, 

 the greater power 

 of the flexor ten- 

 dons stretches 

 the weaker elas- 

 tic ligament, the 

 claw is brought 

 down, and so a 

 powerful grip is 

 obtained. The 

 under-surface of 

 the cat's fore and 

 hind feet is pro- 

 tected by certain 

 hardened pads of 



subcutaneous and fibrous tissue viz. the 

 plantar pad, giving chief support to the leg, 

 and the digital pads pro- 

 tecting the claws, etc. 

 These pads are, of course, 

 of additional use in aiding 

 the cat's noiseless and 

 stealthy progression. 



The cat's hind limb is 

 articulated by a ball and 

 socket joint to the hip-bone 

 or pelvis (20), which is 

 again firmly united to the 

 three bones forming the 

 sacrum D. The thigh-bone 

 or femur (19) sustains the whole body, and 

 has many powerful muscles attached to it 

 concerned in the springing movements so 

 characteristic of the animal ; to its lower end 

 is articulated the principal bone of the lower 

 leg, the tibia (13). At the union of these two 

 bones on the anterior side is the knee-cap, or 

 patella (12). On the outer aspect of the tibia 

 is a slender bone, the fibula (18), its outer end 

 being attached to a prominence on the tibia, 

 the lower end to one of the large bones (the 

 astragalus) which form the, tarsus of the foot. 

 The Tar sal bones (14) consist of seven bones, 

 the largest of which is the os calcis (17), or 

 heel-bone, to which powerful muscles are 

 attached. Succeeding the tarsal bones are the 

 four bones forming the metatarsal bones (the 

 fifth or inner toe being absent, though often 



SKULL, SIDE VIEW 

 JAW IN PLACE. 



