These questions cannot be satisfactorily answered until after a careful 

 survey has been made. 



The importance of this enterprise cannot easily be overestimated, and 

 the cost of the work, even if it should reach millions, will be insignificant 

 in comparison with the results to be obtained. 



Explorations of Mt. Orizaba. By J. T. Scovell. 



Variations in the dynamical conditions during the deposit of the kock 

 BEDS at Richmond, Ind. By Joseph Moore. 



The relation of the keokuk groups of Montgomery county with the 

 typical locality. By C. S. Beachler. 



Comments on the descriptions of species. By C. S. Beachler. 



On a deposit of vertebrate fossils in Colorado. By Amos W. Butler. 



Topographical evidence of a great and sudden diminution of the an- 

 cient water supply of the Wabash river. Bv J. T. Campbell. 



Source of supply to medial morains probably from the bottom of the 



GLACIAL CHANNEL. Bv .J. T. CaMPBELL. 



