CHAP, iv.] THE SKELETON OF THE LIMBS. 



103 



open forwards, and when the body is supported as in walking the 

 fore- legs are in pronation. 



The skeleton of the _ fore-leg below the elbow is divisible into a 

 tri- and a bi-digital series, placed side by side. 



Thus there is, first, the radius ; the scapho-lunar bone ; the 



Fig. 63. DIGIT OF FORE-PAW, WITH ITS LIGAMENTS. 



gament which passes from 

 above the root of the claw, downwards and 

 backwards to the distal part of the second 

 phalanx ; also the long flexor tendon (which 

 by being pulled backwards draws down the 



claw) passing through the ligamentous loop 

 attached to the under surface of the middle 

 phalanx. The sesamoid bone beneath the 

 distal end of the metacarpal is also shown. 



trapezium, the trapezoides, and the magnum ; the first, second, and 

 third metacarpals ; and the annexed digits forming the tri-digital 

 series. 



We have, secondly, the ulna ; the cuneiform ; the unciform ; the 

 fourth and fifth metacarpals ; and the corresponding digits forming 

 the bi-digital series. 



THE SKELETON OF THE PELVIC LIMB. 



11. The bones of the cat's PELVIC LIMB are divisible (like those 

 of its pectoral limb) into three categories : A, that of the hip ; B, 

 that of the hind-leg ; and C, that of the hind-foot. 



A. The skeleton of the hip, or haunch bone, is called the os 

 innominatum ; and there is one such on either side in the adult 

 animal. 



B. The skeleton of the leg is sub-divisible into (a) that of the 

 thigh, which consists but of one bone, called the femur ; (b) that of 

 the lower part of the leg, which consists of two bones placed side by 

 side. The larger of these is called the tibia ; the other, much more 

 slender and placed on the outer side of the leg, is called the fibula. 

 It is also called the peroneal bone of the leg, because it clasps, as it 

 were, the larger bone. 



C. The skeleton of the hind-foot, like that of the fore-foot, is 



