1875.1 400 [Sterenson. 



Why the palseo-botanist should put these plants into the Eocene, rather 

 than into the Miocene, is not known, unless it be done in deference to the 

 stratigraphy. 



Other illustrations might be given, such as the occurrence in the Ameri- 

 can Carboniferous, of types which in Europe are Triassic or Jurassic, but 

 it is hardly necessary. It certainly seems clear to me from the showing 

 of the pala30-botanists themselves, that the plants have nothing to do 

 with the matter ; that the fact that certain forms occur at a certain hori- 

 zon in Europe is no evidence, pro or con, that their horizon in America 

 is equivalent to that in Europe, The dicotyledonous leaves of the Lig- 

 nitic Groups, i. e., the Dakota and Fort Union, are locally of service, in 

 that by them we may not infrequently trace the formation on both sides 

 of extensive areas, from which the rock has been eroded, or in localities 

 where the stratigraphical relations are d oubtful. 



It appears, then, by the common consent of all, that we must determine 

 the European equivalents of our strata by means of animal, not by means 

 of vegetable remains. This being understood, we may look at the facts 

 as we have them. 



The Lignitic areas are two, one on the west coast, and the other in the 

 Rocky Mountain Region. The history of these is different, and they re- 

 quire to be taken up separately. 



Lignites of the Pacific Coast. 



According to Mr. Gabb, the lignites occur at three horizons in this re- 

 gion. At the lowest line are the lignites of Vancouver and the adjacent 

 portions of Washington Territory ; higher up he finds the lignites of 

 Monte Diablo, in California. These contain all the workable lignites. 

 But at a still higher horizon there occurs an extensive deposit of lignitic 

 beds, none of which are of economical value. The last group he regards 

 as of Miocene age, but the others he places in the Cretaceous. 



The California lignites have been sufficiently discussed by the geolo- 

 gists of that State. I do not know that the reference of these to the Cre- 

 taceous has ever been seriously called in question, so that it is unneces- 

 sary to speak of them here. The deposits possessing chief interest for 

 us are those of Vancouver. These have been carefully studied by a num- 

 ber of geologists, and the fossil remains, both animal and vegetable, have 

 received close attention from palseontologists of the highest standing. 

 The deposits of Bellingham Bay, Birch Bay, atd other localities on the 

 continent, can hardly be regarded as fairly coming within the range 

 of this discussion, as the animal remains have not yet been worked up 

 thoroughly. 



According to Richardson, the coal deposit of Vancouver is divided into 

 two distinct fields, one on the east coast, known as the Nanaimo Field ; 

 the other on the west and northwest coast, named by him the Comox 

 Field. Both of these have been examined by him, but his more el aborate 

 work was done in the latter. 



