30 T/<<- American Geologist. Jan. i89i 
form that prevails in Kiowa county. The Bear creek Inoceramus 
is identical with that seen at Belvidere, and near the Blue Cut. 
The absence of Turritella here (complete, so far as yet observed) 
is noticeable. 
On Bluff creek, also in Clark county,* we again find the Neo- 
comian well developed. Passing down the valley, we first meet 
with it in the bed of the creek not far below the old ( Peter Hend- 
erson ) crossing of the Camp Supply trail. It is here overlaid 
with Tertiary ; but at the Thomas ranch, three miles further up 
the creek, occurs a limited outcrop of soft, gray to yellow and 
red sandstone, which is probably a ledge of the Dakota. The 
outcrop below the Camp Supply trail is largely blanketed by the 
sand and gravel of the channel. It consists of slabs of blue 
laminated sandstone, associated with blue and yellow clay mud 
( the latter evidently water-soaked shale) and containing obscure 
fossils, among which I have recognized Gryphcea pitcheri, Tri- 
gonia emoryi, Idonearca vulgaris, Cardium Mllanum, and obscure 
forms supposed to be Cardium Jeansasense, Cyprimeria, Mactra, 
a radiately ribbed Ostrea, ami a large areolated Polyzoan. Im- 
mediately below Vanhem occurs a ledge of shell-breccia of Ostrea 
franklini, Gr. pitcheri, etc. 
Half a mile lower down the creek occurs a forty or fifty foot 
bluff of Neocomian shale (of the usual olive-gray to yellowish 
color in the upper part), with arenaceous laminae in some of which 
Ostrea franklini so abounds as to form a breccia, while others, 
less crowded with fossils, contain this form together with Gr. 
pitcheri, Tr, emoryi, Card, hillanum, Cyprimeria, etc. Other 
lamina? consist of cone-in-cone having curious, circular, shallow. 
funnel-shaped depressions, concentrically ribbed with reversed im- 
brications. The funnels commonly vary from an inch to four or 
five inches across, and are. perhaps, a fourth as deep ; some have 
raised borders of uniform width and are of remarkable symmetry. 
Cone-in-cone is, in general, a common structure in the shales of 
the Kansas Neocomian. 
Some three miles below Vanhem the bluffs forrn^a large amphi- 
theatre, the east bluff rising l'(»0 feet above the creek-bed with 
*For important facilities afforded me by Henry Fares, Esq,, of Fares' 
Ranch, in aid of my geological reconnaissance of (.'lark county, 1 would 
here make grateful acknowledgment. 
