GENERAL CONCLUSIONS 263 



not interfere with the movement by their bulk and yet 

 give tremendous power to the pushing action of the legs. 



Finally, a comparison of the skulls (see Fig. 112) is 

 interesting as an illustration of the progression in size of 

 the brain box, and the increase in intelligence as we go 

 higher in the scale; while the jaws with their teeth modi- 

 fications show every variety of adaptation to different 

 foods and modes of eating. 



General conclusions. — We may note, in conclusion, 

 that the bones of all vertebrate animals are remark- 

 ably similar in arrangement and position, but that ever}'' 

 animal shows modifications in structure and position, 

 that fit his particular framework to his needs. 



