MIRACLES OF SCIENCE 



been known that if a crab or a lobster loses a claw, 

 another claw presently grows in its place. A similar 

 restoration of members may take place in animals 

 still higher in the organic scaled If a salamander, for 

 example, loses its tail or a leg, the member is pres- 

 ently replaced by a new one precisely like the old. 

 Various reptiles are also able to grow new members. 



On the whole this regeneration of limbs would 

 perhaps not seem mysterious except as all life 

 processes are mysterious were it not that the capac- 

 ity is entirely lacking in all organisms higher than 

 the reptiles. No bird or mammal, either in a state 

 of nature or under the observation of the experi- 

 menter, shows the slightest capacity to reproduce 

 a lost eye or leg, or even the single joint of a toe. 



It is this fact that makes the power of regenerating 

 lost members as exhibited by the lower organisms 

 seem mysterious and wonderful. 



Inasmuch as the higher organisms have developed 

 from the lower forms, it would appear that the 

 capacity to restore severed members is one that has 

 somehow been lost in the process of evolution. In- 

 teresting questions might arise as to just why this 

 has come about. It is not altogether a question of 

 complexity of organization, for the leg of a mouse, 

 tor example, is seemingly no more complex a mem- 

 ber than the leg of a salamander. Indeed the two 

 members are constructed alter the same pattern. 



Perhaps the explanation of the anomaly is to be 

 found in the difference of habit of cold blooded and 

 warm blooded animals. The cold blooded creatures 

 are able to go long periods without food. They very 



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