25: 



THE POPULAR SCIENCE MONTHLY 



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Typical Exposuke uf xiiE Uicakl.u 1'liocexe neah RiCAia.o. ( riiutugraijli by C. L. 



Baker.) 



in the El Paso Eange on the western border of the desert, hut no addi- 

 tional material representing this stage has as yet been found. 



To the whole series of older or Tertiary sediments of the Mohave 

 area, 0. H. Hershey has given the name Eosamond series. Mr. 

 Baker has shown that the series is divisible into a number of quite dis- 

 tinct divisions. Some of these may rejoresent quite widely separated 

 periods. Evidence which the writer obtains from a study of the faunas 

 indicates that the deposits north of Barstow containing a Miocene 

 fauna, may represent a formation quite distinct from that at Kicardo 

 containing a Pliocene fauna. The term Barstow formation is used 

 for the beds containing the Upper Miocene fauna. The lower portion 



Exposures op. Ricaedo Pliocene, Showing Chaeacteristic Bad-land Structure in 

 Outcrops near Ricardo. (Photograph by C. L. Baker.) 



