EXPLORATIONS IN NEBRASKA AND DAKOTA. 



CATALOGUE OP THE COLLECTIONS 



GEOLOGY AND MTUEAL HISTORY, 



OBTAINED BY 



THE EXPEDITION UNDER COMMAND OF LIEUT. G. K. WARREN, 



TOPOGRAPHICAL ENGINEERS, 



F. y. HAYDEN, M. D. 



Washington, D. C, Novemler 28, 1858. 



SiK : In compliance with your request I have prepared a catalogue 

 of the collections in geology and natural history, obtained in Ne- 

 braska and portions of Kansas, during several expeditions to those 

 Territories under your command. 



The list cannot be made out at this time as complete as could be 

 desired, but it will be at once evident to all that the amount of new 

 and valuable material thus secured, will, when properly studied and 

 illustrated, form a large and positive addition to science. Of the 

 fossil mollusca collected most of the new species have been indicated in 

 scientific journals by my associate, Mr. Meek, and myself, and about 



