288 



ANIMAL BIOLOGY 



the longer bones of the arms and legs are hollow. With 

 a given amount of material the greatest strength is secured 



Frontal bone 



Parietal bone 



Temporal bone 



Malar or cheek bone 



Lower jaw 



Clavicle 

 Humerus 



Nasal bones 

 Upper jaw 



Carpals 

 Metacarpals 



Phalanges 



Sternum 



Pelvis 



Ligaments 



Tarsus 



Metatarsus 



Phalanges 



FIG. 207. Skeleton. 



if it is in the form of a hollow tube, and Nature has taken 

 advantage of this principle in the formation of the skeleton. 



