22 GEOLOGICAL SUEVEY OF THE TERRITORIES. 



differences at different degrees of latitude, and at tlie same time recog- 

 nizes identity of the characters of this vegetation at wide distances 

 under the same latitude. 



5th. It shows a more intimate relation between the present flora and 

 that of the Tertiary by the discovery of new types identical in both. 



The outlines of our Tertiary formations are, from former researches, 

 recognized by their flora in Vancouver, Oregon, Alaska, Greenland, 

 Connecticut, Kentucky, and Mississippi. Under the systematic and 

 judicious directions of Dr. Hayden, its central area is diligently studied 

 in the Northwestern Territories, and every year adds to the value and 

 the importance of the materials furnished for the study of its fossil 

 vegetation. And now Professor J. D. Whitney sends from California 

 a large number of specimens obtained there from the Cretaceous and 

 from different stages of the Tertiary formation. We may thus foresee 

 that in a short time North America will contribute for the acquaintance 

 of the flora of these formations documents reliable enough to afford a 

 secure basis for its detailed and comparative history. 



•GoLUMBUSj Ohio, May 4, 1872. 





