Where did Life Begin? 41 



only found now in the tropics, and were once 

 living in the Arctics, it follows that unless they 

 came from the Arctics originally they must 

 have travelled over and receded from a part or 

 all of the distance and territory between the 

 tropics and the Arctics, and in that event a 

 warm climate, suitable for them, must have 

 moved northward with them, or at the time 

 of their northward movement the climate of 

 the Arctics must have been warmer than the 

 tropics to have invited them, which is assum- 

 ing one useless phenomenon and two improba- 

 bilities to account for that which is quite easy 

 of solution in the natural order of things, 

 and without recourse to either. 



In all cases where the remains of identical 

 forms are found in localities thus distant from 

 each other, one of two conclusions seems in- 

 evitable : either one came from the locality of 

 the other, or they both had a common ances- 

 try located in some other place. In either 

 case the species must have travelled as far, at 

 least, as the entire distance between the places 

 where their remains are found ; and if they 

 had a common ancestry located anywhere ex- 



