304 GEOLOGICAL SUEYEY OF THE TEEEITORIES. 



Arctic facies. The two other species have, as yet, relation only with other 

 plants from the Quadersandsteiu of Europe. A7'alia quinquepariita, 

 Lsqx., is a relative of A.formosa, Heer, from 3Ioleteiu. The author com- 

 j)'ares it to A. primigenia, from Mount Bolca, a locality well known by 

 its fossil flora, which, though referred to the Eocene, has some typical 

 Cretaceous forms. Quercus Mudgii, Lsqx., as remarked in its descrip- 

 tion, is comparable to Castanea Hausmanni, i)ublished by Dunker, from 

 the same formation (Quadersandsteiu) of Bhmkenburg. 



Do the four species which have been described, from the locality 

 three miles above Spring Caiion, bear an evident Cretaceous facies ? 

 This locality is in the neighborhood of strata bearing remains of Ter- 

 tiary plants, and this inquiry is forced by the presence of Cretaceous 

 types at a station where they were unlooked for. The first of these 

 species, referred to Sequoia Eeichenhachi, Heer j from the Cretaceous of 

 Cone, Greenland, is identical in characters, except in the dimiuutive 

 size of the form represented by our specimens. This difference in 

 the size of branches and leaves of conifers cannot be considered 

 as specific, especially for i)lants of a same geological formation. 

 The second form, referred to Andromeda Farlatori, lleer, from the 

 Cretaceous of ]S^ebraska, is represented by an entire leaf, better 

 l)reserved than any specimen as yet obtained of it, and, therefore, I con- 

 sider its identification as certain. The third. Magnolia alter nans^ Heer, 

 also formerly obtained from is'ebraska, is a mere fragment, and on that 

 account its ideutitj' ufight be disputed. The fourth, Pliyllocladus suhin- 

 tegrifolius^ has not yet anj^ relative in the Tertiary- formations; and, 

 therefore, even omitting the third species as doubtful, Ave have still 

 three distinct Cretaceou's forms, aflbrding evidence to the age of the 

 strata where they have been found. According to the indications 

 kindly furnished by Dr. Hayden, these strata are either in the lowest 

 part of the Tertiary strata of the West or in the upper part of the 

 Cretaceous, there being still a great thickness of measures between the 

 Kansas or Nebraska leaf-bearing Cretaceous strata and those of Spring 

 Caiion. It seems, therefore, that we may come to the conclusion : first, 

 that there is still a succession of vegetable representatives of our 

 Cretaceous flora, ascending much higher in these measures than at the 

 localities where the first remains of this flora were obtained; secondh', 

 that if it is the case, avc may expect to find in those intermediate strata 

 representatives of transitional forms from our Cretaceous species to 

 those which have been found and described from the so-called disputed 

 strata, necessarily considered, from the characters of their vegetable re- 

 mains, as of Tertiary age. The examination of the intermediate measures 

 is, therefore, of great interest, as from the modifications of typical forms in 

 these measures, supposed successive in time, we ma3' find facts proving 

 a series of changes, or of specific forms, under appreciable influences. 



III.— TERTIAPvY FLOExl OF XOETH AMERICA. 



§1. General Eemarks. 



In the introduction .of a i)amphlet recently published by Professor 

 Heer, " On some Fossil Plants of Y^ancouver and British Columbia," the 

 author remarks that ''while we are now acquainted with a large num- 

 ber of species of fossil plants from the Miocene of Europe, we know 

 scarcely any from the same formation of America. And yet this 

 knowledge would be most valuable to science, as it would give us, on 

 the history of the vegetable world, on the origin and succession of 

 vegetable types, on the relation of the Tertiary flora of America with 



