376 GEOLOGICAL SUEVEY OF THE TEREITOEIES. 



Mass., a palm ; Lomatia Bolcensis, TJ. ; L. latior, Heer, of wliich a small 

 broten part is figured in the Baltic Flora, and to wliich one of the most 

 abundant species of Black Butte Myrica Torreyi, Lesqx., so much resem- 

 bles by its peculiar nervation and by the form of the leaves that bet- 

 ter specimens only of the European plants can decide between positive 

 identity or a very close relation ; Myrica MenegMni, U.. of a type repre- 

 sented with us in the Upper Tertiary of South Park ; and Baijhnogene 

 Yeronensis, Mass., which Schimper compares to Cinnamomum ScJieuch- 

 zeri. This is all that is positively known of the flora of Mount Bolca. 

 It is impossible to consider it as a kind of typical flora of the Eocene of 

 Europe, and to assert that if we cannot point out any of our Lignitic 

 species as identical with this flora, it is for that reason deprived of the 

 character of the Eocene vegetation. 



France has in the deposits of the old Travertins of Sezane a number 

 of species whose types seem to be intermediate between the Cretaceous 

 species and those of the Upper Eocene. This flora is known by the 

 admirable work of Count Saporta,* who describes in it a Sassafras 

 comparable to 8. Mudgii, and leaves of Magnolia, related to 3L alternans 

 and M. capellini, three species described from the Dakota group. A 

 number of forms of this Lower Eocene flora are also related to the Ter- 

 tiary species of Europe, especially to those of the Mount Promina flora ; 

 and with our Lignitic flora it has closely allied two of the more charac- 

 teristic and more abundant species of Black Butte, Sterculia variabilis, 

 Sap., distinguishable only from Ficus planicostata by the unequal lateral 

 base of the European leaves, and the beautiful Viburnum giganteum, 

 related, by its size and nervation, to V. marginatum. Besides this, it 

 has Aspleniwn subcretaceum, Sap., intimately related to the species which 

 I have described as Sphenopteris eocenica, most abundant at Golden ; 

 .Cissus primmva to G. lohato-crenata, also abundant at Black Butte and in 

 the Colorado Lignitic basin. Mount Brosse, &c. ; Cornus platiphylla, re- 

 lated to G. impressa. These all show affinity indeed to a flora so posi- 

 tively marked as Lower Eocene, that some of its types are still Cre- 

 taceous. 



I have admitted, as indication of the Eocene age of our Lignitic flora, 

 the great abundance of fucoidal remains, or of marine plants, in the 

 underlying sandstone of the Lignitic, a character remarked in the sand- 

 stone of Mount Bolca, and also of the Flysh of Switzerland. One of the 

 few species which I have as yet been able to describe, from the difficulty 

 of obtaining specimens, Halimenites minor, is known from this last for- 

 mation. Besides this, a comparatively large number of species of ferns, 

 some of them identical with species of Promina: Goiiiopteris polypodioides, 

 Ett., and Splienopteris eocenica, or with that of Boernstadt: Biplazium 

 3iuelleri; then a great proportion of remains of palms, referable to as 

 many species as have been described from Europe at least, ssome of them 

 identical with species of Promina, Boernstadt, Haring, representing, like 

 Flahellaria latania, F. longirachis, F. Zpilceni, some of the more ancient 

 forms of palms recognized in the Ctenzoic times. The remarkable prepon- 

 derance of palm remains has been mentioned from all the stations of the 

 Lower Lignitic where fossil plants have been discovered : Vancouver, Fort 

 Union, Black Butte, Golden, Sand Creek, Gehrung'a, Canon City, Eaton 

 Mountains, Placiere, the Mississippi, &c. They have given to the vege- 

 tation of the epoch a subtropical character, marked still by a number of 

 species of Ficus of the broad-leaved and palmately- three-nerved group, 

 most of them new species, and none of the typeof the lanceolate-pinnately- 

 nerved leaves like Ficus lanceolata, F. multinervis, &c., which, with us 



* Prodrome d'une flore fossile des Travertins anciens de Sezane, (1363.) 



