32 ANIMAL PHYSIOLOGY. 



i 



placed that its upper end is thrown in front of the rest of it, 

 and that its hinder surface, which is narrower than the 

 anterior, looks upwards; it would, therefore, fall down into 

 the pelvis were it not supported by a pair of exceedingly 

 strong posterior sacro-iliac ligaments ; and it is through 

 these ligaments much more than by direct pressure that 

 the weight of the body is conducted from the sacrum to 

 the pelvis. 



Fig. 13. SECTION" OF PELVIS, showing the suspension of the sacrum 

 between the haunch bones, a, the posterior sacro-iliac ligaments. 



16. The thigh-bone or femur corresponds with the humerus 

 of the upper limb ; in front of the knee is the patella or knee- 

 cap, which is a sesamoid bone or ossification within a tendon, 

 and not at all correspondent with the olecranon of the elbow : 

 in the leg the tibia and fibula are the bones corresponding 

 with the radius and ulna in the fore-arm; and in the foot 

 there is a close correspondence of all the bones with those of 

 the hand. 



The parts of the foot are called the tarsus, metatarsus, and 

 phalanges. The phalanges and metatarsal bones are arranged 

 quite like those of the hand, the great toe being similar to the 

 thumb in having only two phalanges. The bones behind the 

 metatarsals are the internal, middle, and external cuneiform 



