XVI II.] PRIMATES. 301 



tibia, an ossification of the internal interarticular semilunar 

 cartilage. 



Special Characters of the Bones of the Thigh and Leg in the 

 various Groups. 



In Man, the femur (see P'ig. 109, p. 298) is long and 

 rather slender, the shaft is curved forwards, the head is 

 large and globular, the neck elongated and narrow. 



In the Gorilla, the femur is much shorter and broader ; 

 the head is smaller and less globular, the neck is shorter 

 and set on the shaft more at a right angle. In the Chim- 

 panzee the femur more resembles that of Man. In the 

 Lemurs it is very slender and straight, the head is globular, 

 and the neck very short. 



The tibia and fibula are distinct, and well developed in 

 all the Primates, and are united with each other only at 

 their extremities. Fabellce are wanting in the highest forms, 

 but generally present in the others. The patella is usually 

 broad and flat, and more or less lozenge-shaped. 



In the terrestrial Carnivora, the femur is straight, mode 

 rately slender, and with rather a small head. The fibula is 

 slender, an.d in the Dogs curved tow^ards the tibia, the lower 

 half being closely applied to that bone ; but in the Bears, 

 and many others, there is a considerable interval between 

 the bones throughout, except at their articular extremilies. 

 Fabellas are generally present. 



In the Seals, the femur is exceedingly short, broad, and 

 flattened, with a globular head and an extremely short neck. 

 The fibula is almost as large as the tibia, especially at -the 

 distal end. These bones are commonly ankylosed together 

 at their proximal extremities. 



Among the InsectiVora, the Hedgehog has a . strong 

 rido^e below the great trochanter of the femur, and several 



