62 



IS relatf^lby Ptero^Mjlhm {?) EmesUnce and Quercus Mudgii, and to that of 

 the same forroafcioiL of Medershcena, as described bj^ Ettinghausen by a 

 Cunninghamites, a GlypfostrohuSy {Frenelites,) and Ficus HalUana. And, 

 too, we have to admit an uncertain relation with Australian types by 

 the species described by Heer as Froteoides, aaiby one leaf of Conifer, 

 FhyllockuUos, a type extinct on this continent. 



This is sufficient to prove, relatively to our present knowledge, at 

 least, fckfi. truth of the assertion, that the flora of the Dakota group, 

 without affllrifeywith any preceding vegetable types, without relation to 

 the flora of the lomQi Tertiary of our country, and with scarcely any 

 forms referable to species-known from coeval formations of Europe, pre- 

 sent in its whole a remarkabfe-aad as yet unexplainable case of isolation. 



