124 ERECT ATTITUDE 



of standing would be just as secure, the transverse base of 

 support being still the same; but progression would be im- 

 peded, as it actually is in the female, from the greater trans- 

 verse diameter of the pelvis. 



Another character of the human femur is the obliquity of 

 its shaft, and superior length of the internal condyle, arising 

 from the breadth of the pelvis, and length of the cervix, 

 combined with the necessity for bringing its lower end per- 

 pendicularly under the pelvis, in reference to the secure sup- 

 port of the trunk. 



The line of direction of the human femur is perpendicu- 

 lar, the same as that of the trunk : its axis coincides with 

 the centre of gravity of the body : it is placed perpendicu- 

 larly under the pelvis, and thus supports the trunk steadily. 

 In all other animals it forms an angle with the spine ; and 

 this is often even an acute one. It is obvious that the erect 

 attitude must be extremely unsteady, and the difficulty of 

 maintaining the body in equilibrio very great in such an 

 arrangement. When the vertebral column is raised per- 

 pendicularly in the orang-utang, the thigh-bones form an 

 obtuse angle with it : the long arms preserve the balance, 

 as they do likewise in the gibbon (S. Lar). The angle is 

 increased in quadrupeds under similar circumstances ; and 

 the efforts they make to remain upright on the hind feet 

 are continued with difficulty, more especially if not assisted 

 by some other advantages of construction, as in the bear,^ 

 for instance, by the length of the heel. 



The feet, being the ultimate supports of the whole frame, 

 and the primary agents of locomotion, are characterized by 

 a combination of greater breadth, strength, and solidity, in 

 proportion to the size of the body, than those of any animal. 

 The whole surface of the tarsus, metatarsus, and toes rests 

 on the ground, and the os calcis forms a right angle with 

 the leg. The two last circumstances are seen in no other 

 animal ; even the simiae and the bear have the end of the os 

 calcis raised, so that this bone begins to form an acute angle 

 with the leg : the dog, the cat, and other digitated quadru- 

 peds, even the elephant himself, do not rest on the tarsus or 



