THE SKELETON 7 



the ribs are joined in the front of the body. In the young 

 of both man and ape it is a mere cartilage. This slowly 

 ossifies as the animal matures. The process appears to 

 begin at five different segments, the first nucleus appear- 

 ing near the top. This bone never becomes quite perfect 

 either in man or ape. It always remains somewhat porous, 

 and even in advanced age the outline of the lower portion 

 is not defined by a smooth, sharp line, but is irregular in 

 contour and merges into the cartilages that unite the ribs 

 to it. 



In an adult human being this bone is usually found to 

 be in two segments, while in the ape it varies. In some 

 specimens it is the same as in man. In others it is some- 

 times found to be in three, four, or even five sections. But 

 the sternum in each is regarded as one bone, and is devel- 

 oped from one continuous cartilage. The separate parts 

 are not considered distinct bones. The reason, no doubt, 

 that this bone remains in separate sections in the ape is 

 due to the stooping habit of the animal, by which the 

 part is constantly flexed and alternately straightened, and 

 therefore discharges its function better than it otherwise 

 could. 



With these trifling exceptions the skeletons of man and 

 ape may be truly said to be exact counterparts of each 

 other, having the same number of bones, of the same 

 general model, arranged in the same order, articulated in 

 the same manner, and performing the same functions. In 

 other words, the corresponding bone in each is the same 

 in design and purpose. The frame of the ape is, as a rule, 

 more massive in its proportions than that of man ; but 



