4() ON THE GEOLOGY AND NATURAL HISTORY 
Feet. 
1. Bluish gray clay, exposing a thickness of about : ; : : : , ‘ . . ee 
2. Hard gray layer of Fusudina limestone, . 2 ‘ _ ; ; , : ‘ : . heey 
3. Yellow laminated clay, - . : : : ‘ : : ‘ ‘ ; ‘ aia 
4, Hard gray argillaceous limestone with wusiithes : : ‘ % 
5. Gray fine-grained argillaceous sandstone with fucoidal a sometimes contains seams of iicmek tod 
6. Gray, green, and blue, rather indurated clay, with sometimes near the base many compact concretions 
of limestone, ‘ : ee 
7. Hard light yellowish gray fooee weal of bluish tinge far in sae the affects of waitin 
Contains Spirifer cameratus, S. Kentuckensis, 8. lineatus, Spirigera subtilita, Orthisina Missouriensis, 
Productus splendens? ; P. semireticulatus? ; P. pustulosus and Fusulina cylindrica, together with columns 
of Crinoids, and spines and plates of Archeocidaris ; also jaws and teeth of Aystracanthus arcuatus, . 15 
8. Dark shale, passing up into gray less distinctly laminated ¢lay;; « ‘ i 5 
9. Hard dark bluish impure limestone, containing Fusulina cylindrica, Swirigera ae eS 
Rogersi, P. Prattenianus, Arca carbonaria ? ; an undetermined Monotis, Allorisma ? Leavenworthensis, 
A. subcuneata, Myalina subquadrata, ignited: granosus, and a large Bellerophon, : ; 13-2 
10. Gray, more or less laminated clay, becoming darker near the upper part, rising above the river, . gees 2: 
Attached to the surfaces of bed No. 9 there is usually from one to two inches of soft 
dark argillo-calcareous matter containing great numbers of Orthisina crassa, With the un- 
determined species of Pecten, Mytilus, Schizodus, Pleurotomaria, &c. 
All this section above No. 7 appears to vary considerably, at different places some of 
the beds being entirely wanting, or presenting quite different lithological characters at 
other localities not far from here. Owing to the dip of the strata and partly to the fall of 
the river, the bed of limestone No. 7, which is elevated eighteen feet above the river where 
this section was taken, rises as much as twenty-five feet above the level of the river at a 
distance of one mile or less below ; and on following the outcrop of these rocks along the 
shore above Leavenworth city, they were found to sink gradually beneath the water, so 
that at Fort Leavenworth landing, two miles above (in a north direction from the exposure 
first examined), all of beds Nos. 8, 9, and 10, as well as two or three fect of No. 7, were 
submerged. Should this dip continue at the same rate, without local undulations, the 
whole of No. 7 must pass beneath the river in less than two miles above the Fort. 
Immediately above No. 1 of this section, we saw no exposure of rock in place, but on a 
small stream about two and a half miles below Leavenworth city, and perhaps one and a 
half miles back from the river, there is an outcrop of soft fine-grained yellow sandstone, 
showing a thickness of twenty-four feet, underlaid by a bed of blue clay, of which a thick- 
ness of about four feet was exposed. We had no opportunity to determine the elevation 
of these beds above the river with sufficient accuracy to form a definite conclusion whether 
or not they hold a position above the section seen near the Leavenworth landing, though 
we incline to the opinion that they come in above it. 
