r.MMO.NS.] 



DENVER TO KANSAS CITY. 447 



mainly of beds of the Tertiary system already described as the Monument 



Creek series, which may include several formations. 



A few miles east of Denver the Denver beds are lost to view, and 

 the surface is formed by those of the Laramie Cretaceous, also occupy- 

 ing a practically horizontal position. The higher elevations to the 

 southward, especially as Limon is approached, areoccupiedbyremnants 

 of theTertiary formations, while the broader valleys often contain local 

 developments of more recent formations. 



From Limon, which is on the Big Sandy creek, a tributary of the 

 Arkansas River, the road takes an easterly course passing on to the 

 head waters of the Republican river, one of the important streams 

 which takes its rise in springs on the plains at a considerable distance 

 from the mountains. Eighteen miles west of Goodland it passes into 

 the State of Kansas, and follows the northern ed^o of the divide 

 between the drainage of the Republican and Solomon rivers nearly to 

 Phillipsburg, which is within the drainage system of the latter stream. 



The surface of the country between Limon and Phillipsburg is, pre- 

 sumably, mostly covered by Tertiary formations of as yet undetermined 

 age, the earlier being a grit or series of sands and conglomerates (sup 

 posed to be Miocene), with a recent marl or loess deposited on its 

 eroded surface. The latter is well seen near Norton, Phillipsburg, and 

 Smith Center. Wherever older Meso/oic outcrops are exposed by 

 erosion of these overlying beds, they are found as a rule to be succes- 

 sively older as one goes farther east. 



Phillipsburg is situated near the eastern edge of the great Tertiary 

 plains. The Tertiary beds which once stretched east of it have been in 

 great part removed by the drainage system of the Republican, Solomon, 

 and Smoky Hill rivers, dust before reaching it a prominent mound, 

 known as the (inverted) Bread Bowl, is formed by a protecting top of 

 The hard, conglomerate grit of the Miocene. Fifteen miles to the north, 

 at Long Island, in what are called the mortar beds of the .Miocene, is 

 the bone bed from which Prof. O. C. Marsh obtained many mammalian 

 remains. 



Farther east, in Smith county (Smith Center, county seat), the beds 

 of Colorado Cretaceous are seen; first, the soft magnesian Niobrara 

 limestone, then occasionally a blue shale. At the crossing of the 

 Republican River, near Scandia, the bloffs are of Fort Benton age. 



Near Belleville, and south from there, the sandstones and colored 

 shales of the Dakota are passed over, but the outcrops are few and 

 inconspicuous. 



Although no outcrops of Mesozoic beds lower than the Dakota have 

 been recognized, red sandstones, which are presumably Triassic, have 

 been pierced in boring for salt along the line of the Kansas Pacific 

 Railway in Ellsworth County, still farther southward, in about the mid- 



