xviii.] PR IMA TES. 33 1 



bone within the joint, lying on the articular surface of the 

 tibia, an ossification of the internal inter-articular semilunar 



cartilage. 



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



various Grotips. 



In Man, the femur (see Fig. 117, p. 328) 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 Chimpanzee 

 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. Fabellae 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, and in the Dogs curved towards 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 extremities. 

 Fabellse 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. 



