xESQUEEEux.] PALEONTOLOGY LIGNITIC FLORA AGE. 369 



stratificatiou was also unconformable to all from the coal westward. But when I find- 

 that as we proceed , east, the superimposed Tertiary beds are getting more and more 

 horizontal, and that in the clays and sandstones above the coal, we see a well-developed 

 resemblance in fossil "plants up to the basalt overflow, I gave up the idea of the Cre- 

 taceous origin of this Lignitic, and the possibility that a salt-water deposit could belong 

 to the same geological horizon, as indicated by the Tertiary fresh-water deposits, par- 

 ticularly as the conformability of this coal and this Cretaceous limestone can nowhere 

 be shown. As to Dr. Leconte's report of what I found east of Pike's Peak, it is in 

 the main true. I found coal when on a scout. I judged it was nine feet thick. It 

 seemed almost horizontal, but I would not say it was horizontal, as it was badly cut 

 up by the drainage of the small gully we found it in. In bluff's north or northwest I 

 found several Baculiies that seemed to come from a clay -bed in the bluff's ; but whether 

 this coal was superimposed to this baculite clay, or the clay was over the coal, I could not 

 say positively either way. Southwest of this locality, twenty-five miles, oii the Arkansas, 

 the Baculite claj^-beds are below the Inocei-nnms limestone, and no coal whatever above. 

 3d. The coal-bed opened near Platte Cafion I have not yet seen. I know that fine 

 Baculiies and Scapliites have been obtained there, said to be near the coal, but have no 

 evidence of it ; will visit and report to you, as soon as I can, just what I find there. 

 But I think it is a case of local inversion, as the coal, to within three and one-half miles 

 of South Platte Kiver, is tilted up the same as at Bear Creek, Golden, Ralston, &c. 

 Eleven miles north of Golden, on Coal Creek, these Lignitic beds are regularly inclined 

 east, and no Cretaceous beds west of them can I find. At Murphy's coal-mine no Cre- 

 taceous fossils are found east of the coal. In Golden, cutting a deep well in the green 

 Tertiary clay about 1,000 feet east of the coal has exposed a stratum of deep-green clay, 

 with a large deposit (leaf-bed) with leaves changed into glossy coal. They seem to 

 belong to Salix, Platanus, Bliamnus, &c. ; a gramen, also a small fragment of an elytra, 

 or wing-case of an insect. The fossil beds near Bowlder County are accompanied with 

 clay full of casts of leaves, of sedges and grasses, mollusks, fossil turtles, and one or 

 two bones that Professor Marsh thinks are Dinosaurus\ 



This is sufficient to show that, except the specimen of Inoceramus 

 found by Dr. Leconte at the Eaton over.Lignitic beds, no Cretaceous 

 fossil mollusks have been found till now in the whole Lignitic basin 

 from the Eaton Mountains to Cheyenne. 



3d. To answer the objections that at Black Butte, Coalville, Bear 

 Biver, and other localities in Wyoming, the Lignitic beds and sandstone 

 bearing plants had been recognized underlying strata 'with fossil remains 

 of Cretaceous animals, I had to examine if, from its nature and its fossil 

 plants, the Lignitic formation should be of necessity recognized as a 

 whole, or if it could be separated into different members, the one repre- 

 senting the Upper Cretaceous, the other the Lower Tertiary. For this, 

 of course, the essential documents to be considered in the view of my 

 special researches are the fossil plants. From the large number of 

 Fucoids in the sandstone, and from the identity of some of the species of 

 these marine plants found by Professor Meek, even in connection with the 

 lower strata of the Lignitic as far down as the arenaceous beds of Bear 

 Creek and Coalville, with Cretaceous animal remains ; from the prodi- 

 gious preponderance of palms, leaves and fruits, recognized also in the 

 same circumstance, &c., I forcibly admitted the unity of the Lignitic 

 formation in its whole, and therefore limited the discussion to this point : 

 the Cretaceous or the Tertiary age of the formation. The detailed exam- 

 ination of the fossil plants of the Lignitic and of their distribution affords 

 more evidence on this question. 



4th. To strengthen my position in regard to the conclusions afforded 

 by vegetable remains, I compared the Lignitic formations to those of the 

 Carboniferous epoch, remarking that, having positively a preponderance 

 of land-plants or a land-character, they should be considered as a land- 

 formation j that in every formation, especially in every land-formation 

 like that of the Carboniferous, the fossil animal types are more or less in ^ 

 discordance with the vegetable forms in regard to the data furnished 

 by them on the age of the formation. As in the Carboniferous we find 

 Devonian mollusks far above the millstone-grit, and also Permian shells 

 far below the Permian, and as the Carboniferous is now generally recog- 

 24 G s 



