Hayden.) 294 [December 



lieved that this portion of the country formed the western rim of the 

 great coal basin, and that the coal beds had so thinned out in their 

 western extension, that no seams will be found thick enough to pay 

 the cost of opening. At Omaha City the Pacific Railroad Company 

 are sinking an Artesian "Well several hundred feet, with the hope of 

 passing through a bed of coal, but it is hardly probable that they 

 will succeed. 



The Permian rocks of Kansas are also quite instructive. Their 

 organic remains show clearly that these beds are only a prolongation 

 of the Carboniferous period, and as such they are classified in Dana's 

 Manual of Geology. There is no physical break between the well- 

 known Carboniferous beds and those of the Permian ; and the well- 

 known Coal measure fossils gradually fade out, and the well-marked 

 Permian forms increase, as you pass upward, until only about 200 

 feet of rocks contain exclusively Permian forms. This is an impor- 

 tant lesson in geology, inasmuch as there seems to be a bridging over 

 of one of the chasms or breaks in the great divisions of the geologi- 

 cal scale. 



The Dakota group also presents an instructive lesson in the angio- 

 sperm dicotyledonous plants, which have been preserved in its strata. 

 It is well known to geologists that up to the present time no well- 

 marked dicotyledonous plants have been found in rocks older than 

 the Cretaceous. The sandstones of this group at Tekama, Blackbird 

 Hill, Sioux City, have yielded a large number of species. Here 

 leaves were first detected by Dr. H. in 1857. at Blackbird Hill. Not 

 long after this time Mr. Meek forwarded some tracings of these leaves 

 to Prof. 0. Heer, of the University of Zurich, Switzerland, one of 

 the most eminent authorities in fossil botany in Europe. He at once 

 pronounced them of Tertiary age, and on the strength of that opinion 

 Mr. Marcou published a small memoir, in which he affirmed that 

 Mr. Meek and Dr. H. had confounded strata of different ages, and 

 that the plants must have come from Tertiary rocks. 



In 1863, Mr. Marcou. accompanied by an eminent Italian geolo- 

 gist, Prof. Capellini, of the University of Bologna, made a tour to 

 the West, ascending the Missouri River as far as the mouth of the 

 Big Sioux River; and on their return to Europe, published the re- 

 sults of their observations in two small memoirs, in which they both 

 freely acknowledged the correctness of the previous labors of Mr. 

 Meek and Dr. H. Prof. C. made a fine collection of plants from the 

 Dakota group, which he placed in the hands of Prof. Heer, for ex- 



