SOME PREHISTORIC ANIMALS 



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the animal. It also tells us what the animal fed on 

 and what were its habits. By a miracle of sagacity 

 it resuscitates, so to speak, the ancient, dislocated 

 carcass, and makes it live again to the mind's eye. 



"Fossil bones are commonly found embedded in 

 stone quarried at considerable depths; it needs the 

 work of pick and chisel and hammer to free them 

 from the rock. How did they come to be there? 

 In the same way as shells. If the creature lived in 

 the waters of a lake or of the sea, the mud at the bot- 

 tom covered the body after death. If it lived on 

 land, the floods swept away its 

 carcass and bore it to the river, 

 which in turn carried it to lake or 

 ocean. Later the lake dried up or 

 the ocean receded, and the hard- 

 ened clay left behind became the 

 stone whence to-day are obtained 

 the relics of prehistoric forms of 

 animal life. 



"What, then, were these pre- 

 historic forms of animal life that 

 preceded man? Eegarding our- 

 selves as related to the animals 

 provided with bones, a sort of inner 

 framework sustaining the cor- 

 poreal edifice, we may say in a 

 general way that there has been a 

 gradual succession from lower to 

 higher in structure. First appeared the fishes, then 

 came the reptiles, next the birds, after them the 



Skeleton of 



Pterichthys 



