480 KANSAS CITY REVIEW OF SCIENCE. 



its occurrence, and to determine this, resort must be had to preceding life, or to 

 synchronous air-breathing animals which may have been carried out by ocean 

 currents and buried under their deposits. 



The absence of life, or the fossil remains of life of this era are not to be 

 wondered at when we consider the wide-spread destruction which took place in 

 it. All of the lime rocks which were torn from their beds were destroyed, utterly, 

 either by the chemical action of the acids in the water, or ground up by the attri- 

 tion caused by waves and currents, or, most probably, by both of those 

 causes combined, and carried away, in part, to distant and deeper waters, and 

 in part left to form the soils of the local valleys. The more enduring silica was 

 rounded by the action of the water and left in the beds so widely distributed 

 over the country. 



Where the destroyed strata were composed of limestone alone, no pebbles 

 are be found, but where the lime rocks contained masses of chert, or where the 

 strata were composed of chert entirely, the pebbles are found, and the beds vary 

 in thickness in proportion to the amount of material torn down. Where the de- 

 stroyed strata are in a locality of sand rock, and composed of sand rock alone, 

 the gravel beds are composed of their fragments alone. There may have been, 

 and undoubtedly there was, some drifting together of the pebbles, caused by the 

 waves and currents of the sea, but in the main they are confined to the locality 

 where they were torn down, and are nowhere of any considerable thickness. 



There are now in the museum of the University of Kansas perhaps a hundred 

 specimens of fossil shells collected from these beds at various and widely separ- 

 ated localities, identical with the undisturbed fossils of the respective localities 

 where they were found, and which prove conclusively, if additional proof were 

 needed, that the pebbles composing these beds are but the more enduring parts, 

 or silica, entering into the composition of the local rocks destroyed. The silica, 

 being impervious to the acids which aided the destruction of the lime rocks, 

 remains imbedded where showered down from the general ruin, and as left when 

 the land emerged from the water except where the beds have been since locally 

 altered, to a limited extent, by rivers and other streams of water cutting through 

 them. 



r am aware that erosion, and changes in the elevation of land of continental 

 extent occurred during Post Tertiary time; but it is not probable that all the 

 changes happened at the same time, and we must look to the respective changed 

 localities, to determine the relative ages when this work was done. In this 

 paper I have considered southeastern Kansas only, and have attempted to 

 sketch the condition of things wrought out by natural forces in it. 



Note. — This subject will be continued in the next number of the Review. 



