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generally, speckled or veined with red, are seen cither alternating with or 

 underlying banks of coarse, dark yellowish, easily disintegrating sandstone. 

 At one place, near a small branch of tie Blue, such a bank of sandstone, 22 

 feet high, and perpendicular, has its sides hidden by thick strata of that soft 

 clay, forming on both sides gentle slopes to the creek. The preponderance 

 of this clay, which either covers the underlying strata and hides them, easily 

 invaded as it is by vegetation, or which, removed by water erosions, is replaced 

 by materials of transportation, renders more or less obscure or ill-defined the 

 line of superposition of the two formations. Generally, too, the upper mag- 

 nesian limestone is shaly, easily disintegrated, and therefore prepared, like 

 the clay beds, for the formation of grassy slopes. All around Beatrice, even 

 in the town, as, for example, behind the mill, the shaly Permian limestone 

 may be seen exposed in banks overlaid by humus and trees, when at a short 

 distance, and nearly at the same level, the sandstone of the Cretaceous is 

 exposed in a reverse condition, or with its base concealed by detritus or 

 by vegetation. In descending the river for five or six miles from the same 

 place, quarries are seen opened into an inferior member of the magnesian 

 limestone, which is there generally very hard and compact, without any fossi! 

 remains, only mixed with concretions of clay and pyrites. This bed has a 

 thickness of 4 to 10 feet, and passes above into irregular layers of shaly, fos- 

 siliferous Permian limestone, ascending in some places to 30 feet high. In 

 exploring around, up the branches, the superposition of variegated clay or oi 

 sandstone upon the limestone is constantly recognized, though generally, as 

 said above, somewhat indistinct, sometimes a few feet only passing from view 

 or being covered up between the two formations. I carefully observed a 

 number of sections of the same kind in order to ascertain if, in cases of recog- 

 nized and recorded immediate superposition of strata of the two formations, 

 the succession of these strata is always in the same order, and if any traces 

 of materials representing an intermediate formation could be discovered any- 

 where. As far as the researches have been made until now, either by other 

 geologists or by myself, nothing has been seen under the Dakota group but 

 the Permian limestone, with which its lower members are always in contact. 

 A section of a continuous series of the Permian and Cretaceous rocks is ex- 

 posed a few miles south of Beatrice, in a small branch, where a new quarry 

 has been opened for flag-stones, of poor quality. The stone is a magnesian, 

 fossiliferous, shaly limestone, worked down to about 6 feet, where it passes to 

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