NATURAL SCIENCES OP PHILADELPHIA. 19 



arenaceous material is not unfrequently present, it is somewhat remarkable, 

 that dark bituminous shales and beds of coal are rarely met with, even among 

 the outcrops seen along the Kansas, below the mouth of Blue river, belonging 

 to the upper coal measures, and holding a position below the base of the fore- 

 going general section ; while through a considerable thickness of beds belong- 

 ing to higher portions of the coal measures included in the lower part of this 

 section, as well as through the strata containing Permian fossils above, beds of 

 coal and dark carbonaceous shales appear to be almost, if not entirely wanting. 

 It will be observed we have in this general section, without attempting to 

 draw lines between the systems or great primary divisions, presented in regular 

 succession the various beds with the fossils found in each, from the Cretaceous 

 sandstone on the summits of the Smoky Hills, down through several hundred 

 feet of intermediate doubtful strata, so as to include the beds containing Permian 

 types of fossils, and a considerable thickness of rocks in which we find great 

 numbers of upper coal measure forms. We have preferred to give the section 

 in this form because, in the first place, the upper Coal measures of this region 

 pass by such imperceptible gradations into the Permian above, that it is very 

 difficult to determine, with our present information, at what particular horizon 

 we should draw the line between them, while on the other hand, it is equally 

 difficult to define the limits between the Permian and beds above, in which we 

 found no fossils. 



Beginning near the base of this section, we find we have in great numbers 

 the following well known and widely distributed Coal measure fossils, viz. : 

 Fusulina cylindrical Chonetes Verneuiliana, Productus splendens, (or a closely al- 

 lied species,) Retzia Mormonii, Rhynchonella Uta, Spirigera subtilita, Spirifer ca- 

 meratus, S. planoconvexa, and a Euomphalus similar to E. rugosus of the Coal 

 measures, while the few new and undetermined species associated with these, 

 are, tor the most part, also decidedly more nearly allied to Carboniferous than 

 Permian forms. We should here remark, however, that we occasionally met 

 with a species of Monotis, allied to the Permian species M. Speluncaria and Sy- 

 nocladia biserialis, also regarded in the old world as a Permian genus, at horizons 

 far beneath the base of this section, between Manhattan and the Missouri. We 

 even found a single specimen of this Monotis as low down as bed No. 9, of the 

 section taken near the landing at Leavenworth City, which must occupy a 

 position several hundred feet below the lowest beds of the above section. Still 

 as this shell is very rare in these lower rocks, and the Synocladia is a distinct 

 species from the well known Permian form of the old world, while they are 

 both, at these horizons, associated with great numbers of the common well 

 known Coal measure species we can only regard their presence in these beds as 

 establishing the existence of these genera at an earlier period in this country, 

 than in the old world. This, it seems to us, is more philosophical than it 

 would be to place all this great thickness of strata, with their vast numbers of 

 well known Coal measure species, in the Permian, merely because we also find 

 with these occasionally a few forms which would in the old world be regarded 

 as characteristic of the Permian epoch. 



Taking it for granted then, that we have carried this section down far enough 

 to include, not only all the beds containing almost exclusively Permian forms, 

 but a considerable portion of the upper Coal measures, it will be interesting 

 to notice, as we ascend in the series, how far each of the Coal measure species 

 mentioned in the lower part of the section, as well as of a few others that occur 

 above and below, range upwards. Thus we see that Fusulina cylindrica var. 

 Ventricosa, Chonetes Verneuiliana and Retzia Mormonii were not met with above 

 division No. 37 ; while Spirifer planoconvexa,Productus splendens ? and Rhynchonella 

 Uta, were not observed above 34, nor Spirifer cameralus above 32. Fusulina 



* In Russia, Fusulina cylindrica is said to occur only in the upper part of the lower 

 Carboniferous series; but the fossil generally referred to that species in this country, 

 appears to be confined to the Coal measures. We have some doubts in regard to it* 

 identity with the Russian species. 



1859.] 



