OUR BEST FEATURES 



ancestors of the vertebrates, since it gave rise in 

 different groups to horny thorns, to shagreen 

 denticles, to true stratified bony scales, to enamel- 

 covered skull plates, as well as to many different 

 kinds of sense organs. 



Nor can it be too often pointed out that the 

 whole organization of primitive vertebrates was 

 adapted for the pursuit and capture of living prey, 

 that sharp teeth were made from the shagreen of 

 the skin, first for holding and then for cutting 

 living prey, that in every geological age until we 

 reach the primitive anthropoid stock of relatively 

 recent times, the herbivorous forms, derived from 

 the more primitive carnivores, acquired various 

 types of specialized teeth which could never have 

 given rise to the higher carnivorous types. Any 

 hypothesis that would derive the earlier carniv- 

 orous vertebrates from herbivorous predecessors 

 would be definitely contradicted by all the avail- 

 able evidence afforded by a comparative study of 

 the brain, sense organs, the locomotor apparatus 

 and the digestive system. 



After a century of intensive research we can 

 only speculate, almost idly, as to what may have 

 been the mode of origin of the mouth, jaws and 



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