46 ON THE GEOLOGY AND NATURAL HISTORY 
Feet. 
14. Two or three layers of soft fine-grained sandstone, more or less argillaceous, and separated by seams of 
clay, 0 é . 6 . 6 : 6 é . See 
15. Bluish and ash-colored clays, . : : : 6 c : 3 . : . : F eal 
16. Alternate layers of hard bluish gray limestone, and seams of clay with sandy concretions, 8 
17. Rather hard yellowish limestone, with Musudina, : 0 : : é : : : : 523 
18. Ash-colored clay, not very well exposed, . : . . . 5 : : . 0 : . 15 
19. Yellowish impure limestone, with Fusulina,  . 4 : 0 0 0 : 6 0 2 
20. Ash-colored laminated clays—above the creck, . 0 0 . : : : : 0 5 a) 
About three hundred yards below where this section was taken, the creek was observed 
to fall nearly a foot, over a ledge of hard limestone ; and one mile further down, the bed of 
the creek is composed of a hard yellow limestone, containing great numbers of Fusulina. 
At these localities Mill creek is probably not elevated more than thirty feet above the 
Kansas. 
Near half a mile east or southeast of the point where the Fusulina limestone was seen 
in the bed of Mill creek, and at a somewhat higher elevation, we saw apparently the same 
bed of Fusulina limestone, showing a thickness of three feet. Under this there was at one 
place exposed a thickness of some four or five feet of very fine yellow sandstone with 
minute specks of mica. ‘These exposures indicate a moderate dip of the strata towards 
the west or northwest. 
On the north side of the Kansas, in a direction a little west of north, and about sixteen 
miles from the last-mentioned localities, we observed an outcrop, on a small stream marked 
‘“« Last creek” on the maps, presenting the following section, descending : 
Feet. 
1. Seams of yellow magnesian limestone, alternating with clay, showing a thickness of about, —. 6 > 8} 
. Yellow soft granular magnesian limestone, containing Productus Norwoodi, and an undetermined species 
of Myalina, . F : 0 : : ; : o : : 5 c F : : oe ah 
5. Fine laminated black shale, . : 9 : : 0 : : : . . 2 : Rall 
4. Gray rather soft argillaceous limestone, : c . é 5 5 . . . 5 ey al 
5. Blue somewhat indurated very fine calcareous clay, containing at its junction with the next bed below Cho- 
netes, Synocladia biserialis, Cheetetes, and fragments of Crinoids, . 6 2 c ; . > @ 
6. Seams of hard compact gray limestone, alternating with softer argillo-calcareous matter, and containing casts 
of many small Cypricardia-like shells, small Murchisonia, Pleurotomaria, Macrocheilus, Naticopsis, Bel- 
lerophon, &c., : : : ; 0 : ; ‘ 3 ; : : c : ; 504 
7. Bluish laminated clays weathering to drab color, . 0 . 6 ‘ 6 9 . 0 . o 4 
8. Yellow rather soft granular magnesian limestone, with embedded fragments of harder more compact do., . 5} 
9. Bluish indurated caleareous clays, . 5 : : 0 3 
The base of this section is evidently not elevated much above the Kansas, as it extends 
down to the bottom of a deep ravine formed by the creek, while its top appeared to be 
