480 OARBONIFEKUUS FORMATIONS AND KAUNAS OF COLORADO. 



KIRKBYA .lones, l>S(i!(. 



KlRKHYA sp. 



Of this form a .siuirlo specimen has been discovered. The .shell has a sulu'cntral 

 protuberance and two or three heavy concentric furrows. The surface is coarsely 

 reticulate. 



It is evidently related to Klr/iJ/i/n plicata Jones and Kirkby, and is probaTiIy 

 identical with that species. 



Locality and horizon. — Leadville district (station 226.5); Weber formation. 



