312 KEMP AND KNIGHT — LEUCITE HILLS OP WYOMING 



dissected and remnantal lava flows with their flat tops and precipitous 

 escarpments. 



We take up the exposures in a general order from the southeast corner, 

 west and north across them. This order happens also to bring together 

 individuals of related character. 



Mesas without cones 



Black rock Described by Kemp, 



Hatcher Not previously noted. 



North Pilot mesa Described by Cross (?) 



North table Not previously described. 



South table Not previously described. 



Pilot Described by Emmons, Kemp, and Cross. 



Osborn Not previously noted. 



Mesas with cones 



Zirkel Described by Emmons, Kemp, and Cross. 



Emmons Not previously noted. 



Orenda Described by Kemp and Cross. 



Steamboat. . Noted by Endlich but not described. 



Cross Not previously noted. 



Volcanic necks 



Badgers teeth Not previously noted. 



Matthew hill Not previously noted. 



Iddings butte Not previously described. 



Boars tusk Described by Cross. 



Weed butte Not previously noted. 



Hallock butte Not previously noted. 



Dikes 



Wortman dike Not previously noted. 



Iddings dike Not previously noted. 



lulus covered hills 



Endlich hill Not previously noted. 



Hague hill Not previously noted. 



Zirkel Mesa 



GEOLOGY 



This is much the largest of the exposures. It consists of lava flows, 

 with a high and nearly vertical but indented escarpment on the southern 

 side and a deeply dissected one along the northern face. It is a dissected 

 series of lava flows which rest directly on the Laramie, whose beds, richly 

 provided with Ostrea glabra (Meek), outcrop one-eighth of a mile south 



