SWALLOW — MEEK'S NOTES ON GEOLOGY OF KANSAS. 521 



nection with others, and the geologist who neglects it mnst 

 expect to fall into errors, which will ever mar his work. And 

 besides, the line between the Lower Permian and Coal 

 Measures is marked by a striking non-conformability or a 

 " thinning out by erosion" as they call it. But Messrs. Meek 

 and Hayden say there is none, where they make the division. 



If, then, my Lower Permian is not Permian, there is no 

 Permian in Kansas, and Messrs. Meek and Hayden never dis- 

 covered any, and they have made a great ado about nothing, 

 for all the arguments, paloeontological, lithological, and those 

 from non-conformability, are stronger for the lower than for 

 the upper line of separation. 



But Dr. Hayden says there is no want of conforrnability ; 

 that the discordance observed is a "mere thinning out of 

 strata, caused by local erosions." This remark is the more 

 remarkable and important as coming from Dr. Hayden, who, 

 with Mr. Meek, visited the localities at Manhattan and Mill 

 Creek, which I mention as furnishing evidence of non-con- 

 formability. After making a " careful examination" of these 

 localities in 1859, they say that "they are not, so far as their 

 knowledge extends, separated by any discordance of stratifi- 

 cation or physical break," and they further add, "This, how- 

 ever, would be impossible in Kansas.* 



It would seem strange that the absence of eleven distinct 

 strata, measuring over eighty feet in thickness, in one of these 

 localities, which are found in the other, should not be even 

 hinted at, M r hen it was so positively asserted that there was "no 

 discordance of stratification," and that this condition of strata 

 could not produce any discordance ; and quite as strange 

 that the reason why no discordance of stratification was 

 produced by such an erosion was not explained at that time. 

 Had Dr. Hayden then given the lucid explanations contained 

 in his late paper, -j- and shown us what is really meant by con- 

 forrnability, and how that kind of "thinning out " which is 

 "produced by erosion " can not possibly produce any 

 "discordance" or "non-conformability ''j in the strata, I 

 might have been spared the mortification of receiving such a 

 lecture on the elements of Geology, and lost the pleasure of 

 reading so fine a detinition of conforrnability ; § one which 

 contains some ideas which Dana and Murchison had omitted. 



Still, the facts stated respecting the Coal Measures and 

 Permian Rocks in Kansas fulfill all the Doctor's conditions of 



* Acad. Nat. Sci. Phil., 1859, p. 20. 

 t Amer. Jour., July, 1867, p. 33, et seq. 

 \ Acad. Nat. Sci. Phil., Jan. 1859. 

 § Araer. Jour., July, 1867, p. 33. 



