134 GEOLOGICAL SURVEY OF THE TERRITORIES. 



The lignitic beds No. 2 in this section correspond with No. 2 in the sec- 

 tions made near Eoubideau's Creek and station No. 60 (sections Nos. 

 12 and 13). In the section made near station 73 (No. 11) this layer 

 seems to be absent, as it also is in the section made at station 14 on 

 Eoaring Fork. 



It is probably this bed that Dr. Schiel refers to in the Geological Re- 

 port of Captain Gunnison's exploration when he says : " In the Valley 

 of the Blue Eiver, a coal-measure, supported by sandstone, crops out 

 at several places, but the coal does not seem to be of good quality." 



Professor Nevvberry gives the following detailed section made in 

 Arizona : 



Feet. 



1. Coarse yellowish sandstone, with concretions of oxide of iron, and obscure im- 



pressions of dicotyledonous leaves 16 



2. Impure coal, alternating with bands of bituminous shale and fire-clay, con- 



taining fossil-plants — Clathropteris, Cydopleris, Sphenopteris, Pecopteris, 



&c. — all new species 12 



3. Fire-clay and shale 'd 



4. Coarse, compact, white concretionary sandstone G 



5. Green marl 25 



6. Bright red marl ^ 22 



7. White, soft, saccharoidal calcareous sandstone to base 



Layers 3 to 7, inclusive, are probable Jurassic. 



At another point, not tar distant from where the section above was 

 made. Professor Newberry made another section, of which the following 

 is a portion : 



Feot. 



11. Coarse light-yellow or whitish massive sandstone 120 



12. Green shales, with bands of ferruginous sandy limestone and beds of lignite. 



In this group at Oraylee and Camp 96 are Pinna ? lingula (u. sp.) and 

 Gryplicea piteheri ; and over the lignite beds are impressions of leaves of 

 Plotanus, Alnus qaercus, &g., and fossil ferns of the genus SpJienopteris 90 



13. Green, blue, and gray argillaceous shales, with bands of brown or yellow sili- 



ceous limestone, containing Ammonites pericaniiatiis, Inoceramus crispii, and 

 Gryphwa piteheri, var. 7iavia 160 



14. Coarse yellowish sandstone, precisely like Nos. 9 and 11 (base of Cretaceous 



formation ?) 25 



15. Lignitic, (Jurassic,?) better than that above, to base. 



The bed of lignite, which he marks Jurassic! is the layer marked No. 2 

 in the first section given above, while No. 14 corresponds with No. 1. 



Comparing these sections with those I made on the Gunnison River, 

 the lithological similarity is evident. 



I think it probable that his beds of lignite, marked No. 12 in the sec- 

 tion given above, are identical with the layers included under No. 3 in 

 my sections on the Gunnison (Nos. 12 and 13). If so, the bed of lig- 

 nite which he considers as Jurassic is wanting in my sections, while his 

 layers, marked Nos. 13 and 14, correspond to those included in Nos. 23, 

 24, and 25 in section No. 13, made at station 60. It is a curious coinci- 

 dence that the thickness given by him (185 feet) is the same as that given 

 by me. This, however, is no positive proof of identity, as these beds 

 vary in thickness in localities very close to each other. 



If the beds do not belong to the same horizon, I have placed the line 

 of division between the Cretaceous and Jurassic layers lower than Pro- 

 fessor Newberry has done. The specimen of Sassafras that I found in 

 bed 24 of section No. 13, is the only evidence I have upon which to 

 ground such a separation. 



Speaking of the specimen Pecopteris that he found in the lignite bed 

 (No. 2 of his first section given above), Newberry says, "Associated 

 with Clathropteris of Jurassic affinities, and with the first appearing 

 species of the dycofcyledonous plants of the Cretaceous epoch, this 



