OSTEOLOGY OF CARNIVOROUS DINOSAURS. 147 



touched upon. The discovery of more and better preserved materials and the 

 description of specimens already in the collections of our museums will undoubtedly 

 add much to our knowledge of the skeletal modifications that have taken place 

 during successive geological periods. 



Such mechanical progression as has here been recorded is in the direction or 

 adaptation of the skeleton from the generalized to the specialized, thus producing a 

 more efficient mechanism for the particular purpose of speed and destructive power 

 so necessary for the maintenance of life itself. 



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