Early Birds and Mammals 



mammals are mostly known are obtained. It 

 may be readily supposed that tliey could not 

 be gathered in any considerable numbers by 

 crawling about ov^er the ground and laboriously 

 picking them up one by one. True, many are 

 gathered in just that fashion, but far greater 

 numbers are obtained by taking quantities of 

 the sand in which teeth occur and running it 

 through sieves of various sizes. Finally, ants 

 have been pressed into service as collectors of 

 small fossils. These industrious little insects, in 

 digging their long galleries, bring to the surface 

 the grains of sand that are heaped up to form 

 an ant-hill, but they bring up as w^ell the teeth 

 of Cretaceous mammals. It was that skilled 

 paleontologist and unrivaled collector, Mr. 

 Hatcher, who discovered this trick of the ants, 

 and utilized it by digging up many an ant-hill 

 and shipping it East, there to be sifted and 

 sorted at leisure. 



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