154 COMPARATIVE ARTHROIiOQY. , , 



APPENDICULAR SKELETON. 



la the camivora the synovial membrane of shoulder joint is similar to 

 that of the hog in its arranagement. The lateral ligaments of the elhovo joint, 

 together with the annular ligament, form a kind of ring in which the head of the 

 radius slightly revolves, as there is a certain amount of motion between it and 

 the ulna. The radioulnar articulation consists of a superior and an inferior 

 lotatory diarthrcsis, and an interosseous ligament ; the rotatory movements' 

 "between these bones are termed pronation and supination^ the prone being the 

 normal position of the extremity. The metacarpus is formed similarly to that 

 of the hog, but it is more mobile, and the rest of the articulations of the limb 

 lesemble those of that animal, with the exception of the distal interphalangeal, 

 "where we find anteriorly an elastic ligament which acts as the retractor of the 

 claw, and is stronger and much more active in the cat than in the dog, the 

 claw of the former being much more retractile. Posteriorly a piece of fibro- 

 cartilage is the analogue of the navicular bone, which is wanting. 



The patella has one straight ligament, and the menisci are united. In the 

 tibio-fibular articulation, there is superiorly a diarthrosis, otherwise it is formed 

 on the same plan as that of the hog, as is the tarsal joint, excepting that the 

 astragalus has an inferior head instead of a trochlea. 



